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Occurrence of ochratoxin A in grapes, juices and wines and risk assessment related to this mycotoxin exposure

Ocorrência de ocratoxina A em uvas, sucos e vinhos e avaliação de risco relacionada à exposição a essa micotoxina

Abstracts

Ochratoxin A (OTA) is a mycotoxin with nephrotoxic, genotoxic, teratogenic and carcinogenic properties. The presence of this toxin in wines and juices occurs due to the development of toxigenic fungi in grapes. Studies have shown the presence of this toxic secondary metabolite in these beverages may results in economic losses to the winery as well as health problems for consumers. In Europe, several studies have been done in order to map the areas where the development of ochratoxigenic fungi is more favorable. However, in Brazil these studies are still incipient. The Joint Expert Committee on Food Additives of the World Health Organization (JECFA) established the safe tolerable intake of 112ng OTA per kg of body weight per week. To verify whether the population is exposed to OTA levels that pose a risk to health is necessary to compare the parameter of safe ingestion defined by JECFA with the levels of exposure to this toxin. Periodic monitoring of the OTA levels in food and beverage has been justified by some reasons including: (i) the toxic effects of this toxin, (ii) the recent publication of the Brazilian legislation establishing maximum limit for OTA, (iii) the introduction of grape juice in school meals and (iv) the recommendation of regular wine intake because of their functional properties.

mycotoxins; risk assessment; toxic compounds


A ocratoxina A (OTA) é uma micotoxina que possui propriedades nefrotóxicas, genotóxicas, teratogênicas e carcinogênicas. A presença dessa toxina em vinhos e sucos ocorre devido à contaminação das uvas por fungos toxigênicos. Estudos têm mostrado a presença desse metabólito secundário tóxico nestas bebidas, o que pode significar perdas econômicas ao setor vitícola, bem como problemas à saúde dos consumidores. Na Europa, vários estudos têm sido realizados com o objetivo de mapear as áreas em que o desenvolvimento de fungos ocratoxigênicos é mais favorável. Entretanto, no Brasil estes estudos ainda são incipientes. O Comitê de Especialistas em Aditivos Alimentares da Organização Mundial da Saúde (JECFA) estabeleceu a ingestão tolerável segura de 112ng de OTA por quilo de peso corpóreo por semana. Para verificar se população está exposta a OTA em níveis que representam risco para à saúde, é necessário comparar o parâmetro de ingestão segura, definido pelo JECFA, com os níveis de exposição a esta toxina. O monitoramento periódico dos níveis de OTA em alimentos e bebidas é justificado por alguns motivos que incluem: (i) os efeitos tóxicos dessa toxina, (ii) a publicação recente da legislação brasileira que estabelece limite máximo para OTA, (iii) a introdução do suco de uva na merenda escolar; e (iv) a recomendação da ingestão regular de vinho/suco de uva devido as suas propriedades funcionais.

micotoxinas; avaliação de risco; compostos tóxicos


INTRODUCTION:

The grapes are subject to fungal contamination during cultivation, harvest, transport and/or storage. Mycotoxins are products of secondary metabolism of some filamentous fungi. Production of these toxic compounds is influenced by several factors, including humidity, temperature, substrate composition, water activity, pH and fungal strain (MARROQUÍN-CARDONA et al., 2014MARROQUÍN-CARDONA, A.G.. et al. Mycotoxins in a changing global environment - A review. Food and Chemical Toxicology, v.69, p.220-230, 2014. Available from: <http://www.sciencedirect.com/science/article/pii/S0278691514002075>. Accessed: Dec. 15, 2014. doi:10.1016/j.fct.2014.04.025.
http://www.sciencedirect.com/science/art...
). Ochratoxin A (OTA) is a mycotoxin that has nephrotoxic, genotoxic, teratogenic and carcinogenic properties (ROCHA et al., 2014ROCHA, E.B. et al. Mycotoxins and their effects on human and animal health. Food Control. v. 36, p. 159-165, 2014. Disponível: <http://dx.doi.org/10.1016/j.foodcont.2013.08.021>. Accessed: Dez. 14, 2014. doi: 10.1016/j.foodcont.2013.08.021.
http://dx.doi.org/10.1016/j.foodcont.201...
). In this way, the International Agency for Research on Cancer (IARC) has classified OTA in group 2B, ie, as a possible carcinogen to humans (IARC, 1993IARC. Ochratoxin A. In: IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Some Naturally Occurring Substances. International Agency for Research on Cancer, v.56, p.489-521, 1993.). Because of the toxicity of OTA, the maximum limit of 2ng mL-1 was established for grape juice and wine by Brazilian legislation (ANVISA, 2011AGÊNCIA NACIONAL DE VIGILÂNCIA SANITÁRIA (ANVISA). Regulamento Técnico sobre os limites máximos tolerados (LMT) para micotoxinas em alimentos, Resolução RDC n.7, fevereiro de 2011. Diário Oficial da União, Poder Executivo, n.37, 2011.). This same limit is adopted in countries of the European Union (EUROPEAN COMISSION, 2006EUROPEAN COMMISSION (2006). Commission Regulation (EC) n. 1881/ (2006) of 19 December 2006 setting maximum levels for certain contaminants in foodstuffs. Official Journal of European Union, L365, 6 -24.).

The use of grapes that contains OTA for the preparation of juices and wines may be a concern, since grape juices may be widely consumed by children and even are used in school meals in some Brazilian states, such as Rio Grande do Sul and Santa Catarina (RIO GRANDE DO SUL, 2009RIO GRANDE DO SUL. Lei n. 13.247, de 08 de setembro de 2009. Inclui o suco de uva e o suco de laranja produzidos no Estado do Rio Grande do Sul no cardápio da merenda escolar da rede pública estadual de ensino. ; SANTA CATARINA, 2009SANTA CATARINA. Lei n. 14.995, de 16 de dezembro de 2009. Inclui na merenda escolar dos alunos da rede estadual de ensino, suco de uva produzido em Santa Catarina. Available from: <http://server03.pge.sc.gov.br/LegislacaoEstadual/2009/014995-011-0-2009-001.htm>. Accessed: Dec. 14, 2014.
http://server03.pge.sc.gov.br/Legislacao...
). The incentive to grape derivatives consumption occurs due to the presence of phenolic compounds and stilbene which reduce the risk of cardiovascular diseases and have antioxidant and anti-inflammatory properties (XIANG et al., 2014XIANG, L. et al. Health benefits of wine: don't expect resveratrol too much. Food Chemistry, v.156, p.258-263, 2014. Available from: <http://dx.doi.org/10.1016/j.foodchem.2014.01.006>. Accessed: Dec. 03, 2014. doi: 10.1016/j.foodchem.2014.01.006.
http://dx.doi.org/10.1016/j.foodchem.201...
).

The objective of this review was to determine, based on research published in the literature, if the world population is exposed to OTA through the consumption of juices and wines at levels that pose risk to health. The factors related to the development ochratoxigenic fungi in grapes and occurrence of this mycotoxin in the juices and wines were reviewed. The databases used in this research were "Web of Science" and "Scopus" from September 2104 to March 2015. The keywords used for search data were "Ochratoxin wine" and "Ochratoxin juice".

Occurrence and factors related to the incidence of OTA-producing fungi in grapes

The main OTA-producing fungi in grapes belong to the genus Aspergillus. Two sections of Aspergillus are known as OTA-producing: Circumdati(group that belongs the A. ochraceus) and Nigri (group in which are classified A. carbonarius and A. niger). The contamination of grapes with Aspergillus may be minimized by cultivating grapes more resistant to pests and utilization of practices of harvesting and transportation that preserve the integrity of the grapes. The presence of OTA-producing fungi has been occurred in different countries with wine tradition in wine production, incuding Argentina (PONSONE et al., 2007PONSONE, M.L. et al. Ochratoxin A and ochratoxigenic Aspergillus species in Argentinean wine grapes cultivated under organic and non-organic systems. International Journal of Food Microbiology, v.114, p.131-135, 2007. Available from: <http://www.sciencedirect.com/science/article/pii/S0168160506003916>. Accessed: Dec. 20, 2014. doi: 10.1016/j.ijfoodmicro.2006.07.001.
http://www.sciencedirect.com/science/art...
; CHIOTTA et al., 2009CHIOTTA, M.L. et al. Aspergillus section Nigri species isolated from different wine-grape growing regions in Argentina. International Journal of Food Microbiology, v.136, p.137-141, 2009. Available from: <http://dx.doi.org/10.1016/j.ijfoodmicro.2009.08.013>. Accessed: Dec. 20, 2014. doi: 10.1016/j.ijfoodmicro.2009.08.013.
http://dx.doi.org/10.1016/j.ijfoodmicro....
), France (CLOUVEL et al., 2008CLOUVEL, P. et al. Wine contamination by ochratoxin A in relation to vine environment. International Journal of Food Microbiology, v.123, p.74-80, 2008. Available from: <http://www.sciencedirect.com/science/article/pii/S0168160507006873>. Accessed: Dec. 20, 2014. doi: 10.1016/j.ijfoodmicro.2007.12.003.
http://www.sciencedirect.com/science/art...
), Italy (LUCCHETTA et al., 2010LUCCHETTA, G. et al. Occurrence of Black Aspergilli and Ochratoxin A on Grapes in Italy. Toxins, v.2, p.840-855, 2010. Available from: <http://www.mdpi.com/2072-6651/2/4/840>. Accessed: Dec. 15, 2014. doi: 10.3390/toxins2040840.
http://www.mdpi.com/2072-6651/2/4/840...
) and Tunisia (LASRAM et al., 2012LASRAM, S. et al. Ochratoxin A and ochratoxigenic black Aspergillus species in Tunisian grapes cultivated in different geographic areas. Food Control, v.25, p.75-80, 2012. Available from: <http://dx.doi.org/10.1016/j.foodcont.2011.10.006>. Accessed: Mar. 20, 2015. doi: 10.1016/j.foodcont.2011.10.006.
http://dx.doi.org/10.1016/j.foodcont.201...
).

The incidence of OTA-producing fungi in grapes of varieties Bonarda and Tempranillo produced in Argentina was verified by PONSONE et al. (2007PONSONE, M.L. et al. Ochratoxin A and ochratoxigenic Aspergillus species in Argentinean wine grapes cultivated under organic and non-organic systems. International Journal of Food Microbiology, v.114, p.131-135, 2007. Available from: <http://www.sciencedirect.com/science/article/pii/S0168160506003916>. Accessed: Dec. 20, 2014. doi: 10.1016/j.ijfoodmicro.2006.07.001.
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). OTA was not found in grapes, however, several species of Aspergillus were isolated from grapes, including, A. japonicus (40%), A. niger (34%), A. awamori (15%), A. foetidus (4%), A. aculeatus (4%) and A. carbonarius (3%), of these, 24% were identified as OTA producers.

CHIOTTA et al. (2009CHIOTTA, M.L. et al. Aspergillus section Nigri species isolated from different wine-grape growing regions in Argentina. International Journal of Food Microbiology, v.136, p.137-141, 2009. Available from: <http://dx.doi.org/10.1016/j.ijfoodmicro.2009.08.013>. Accessed: Dec. 20, 2014. doi: 10.1016/j.ijfoodmicro.2009.08.013.
http://dx.doi.org/10.1016/j.ijfoodmicro....
) found 284 fungal isolates identified as Aspergillus section Nigri in grapes cultivated in Argentina. A. niger (81%), A. carbonarius (11%) and A. uniseriate (8%) were the species isolated from grapes, that included 32% of OTA-producers (69% of A. niger and 31% of A. carbonarius).

CLOUVEL et al. (2008CLOUVEL, P. et al. Wine contamination by ochratoxin A in relation to vine environment. International Journal of Food Microbiology, v.123, p.74-80, 2008. Available from: <http://www.sciencedirect.com/science/article/pii/S0168160507006873>. Accessed: Dec. 20, 2014. doi: 10.1016/j.ijfoodmicro.2007.12.003.
http://www.sciencedirect.com/science/art...
) observed that the presence of the Botrytis cinerea and Lobesia botrana incresead the contamination by A. carbonarius in grapes grown in southern France, achieving 5.8ng mL-1 of OTA. These vectors damage the surface of the grapes and thus facilitate the colonization of A. carbonarius. LUCCHETTA et al. (2010LUCCHETTA, G. et al. Occurrence of Black Aspergilli and Ochratoxin A on Grapes in Italy. Toxins, v.2, p.840-855, 2010. Available from: <http://www.mdpi.com/2072-6651/2/4/840>. Accessed: Dec. 15, 2014. doi: 10.3390/toxins2040840.
http://www.mdpi.com/2072-6651/2/4/840...
) evaluated the presence of OTA producing fungi in grapes grown in the northern, central and southern Italy. A. carbonarius was found mainly in grapes produced in the south region, while A. niger was predominant in Northern and Central region. The grapes from the south showed more frequent incidence (45%) and highest concentration of OTA (reaching of 9.2ng mL-1 of OTA). The differences in fungal incidence and OTA levels of grapes grown in different regions may occur due to climatic factors of each region. In the southern region of Italy, for example, the climate is more humid and warm and in these conditions, the concentration of OTA in grapes can reach high levels.

LASRAM et al. (2012LASRAM, S. et al. Ochratoxin A and ochratoxigenic black Aspergillus species in Tunisian grapes cultivated in different geographic areas. Food Control, v.25, p.75-80, 2012. Available from: <http://dx.doi.org/10.1016/j.foodcont.2011.10.006>. Accessed: Mar. 20, 2015. doi: 10.1016/j.foodcont.2011.10.006.
http://dx.doi.org/10.1016/j.foodcont.201...
) evaluated the occurrence of toxigenic fungi and OTA in grapes grown in different regions of Tunisia. A. niger was the predominant specie isolated from grapes (75%), followed by A. carbonarius (22%). However, only 3% of A. niger showed potential to produce OTA, while 97% of A. carbonarius were OTA-producers. OTA was found in 38% of grapes in levels ranging from 0.05 a 5.85ng mL-1.

The ochratoxigenic effect of A. carbonarius was evaluated in damage and undamage grapes by BELLÍ et al. (2007BELLI, N. et al. Skim damage, high temperature and relative humidity as detrimental factors for Aspergillus carbonarius infection and ochratoxin A production in grapes. Food Control, v.18, p.1343-1349, 2007. Available from: <http://dx.doi.org/10.1016/j.foodcont.2006.02.014>. Accessed: Dec. 15, 2014. doi: 10.1016/j.foodcont.2006.02.014.
http://dx.doi.org/10.1016/j.foodcont.200...
). These grapes were storage at 20 and 30ºC and humidaty of 80, 90 and 100%. The higher levels of OTA were found in damage grapes, storage at 30ºC and 100% of humidity.

Occurrence of OTA in grape juice and wine

After cereals, juices and wines are the largest sources of exposure to OTA. Since OTA was first detected in these beverages sold in Switzerland (ZIMMERLI & DICK, 1996ZIMMERLI, B.; DICK, R. Ochratoxin A in table wine and grape juice. Occurrence and risk assessment. Food Additives and contaminants, v.13, n.6, p.655-668, 1996. Available from: <http://dx.doi.org/10.1080/02652039609374451>. Accessed: Dec. 15, 2014. doi: 10.1080/02652039609374451.
http://dx.doi.org/10.1080/02652039609374...
), several studies about the occurrence of OTA are found in the literature (Table 1 and 2). The concentration of OTA in juice and wine is often reported below of legislation limit (2ng mL-1) (WOESE, 2000WOESE, K. Ochratoxin A in grape juice and wine. Mycotoxin Research, v.16, p.132-135, 2000. Available from: <http://dx.doi.org/10.1007/BF02943001>. Accessed: Dec. 15, 2014. doi: 10.1007/BF02943001.
http://dx.doi.org/10.1007/BF02943001...
; NG et al., 2004NG, W. et al. Ochratoxin A in wine and grape juice sold in Canadá. Food Additives and Contaminants, v.21, n.10, p.971-981, 2004. Available from: <http://www.ncbi.nlm.nih.gov/pubmed/15712522>. Accessed: Dec. 15, 2014. doi: 10.1080/02652030400000653.
http://www.ncbi.nlm.nih.gov/pubmed/15712...
; ROSA et al., 2004ROSA, C.A.R. et al. Occurrence of ochratoxin A in wine and grape juice marketed in Rio de Janeiro, Brazil. Food Additives and Contaminants, v.21, p.358-364, 2004. Available from: <http://dx.doi.org/10.1080/02652030310001639549>. Accessed: Nov. 15, 2014. doi: 10.1080/02652030310001639549.
http://dx.doi.org/10.1080/02652030310001...
; SHUNDO et al., 2006SHUNDO, L. et al. Ochratoxin A in wines and grape juices commercialized in the city of São Paulo, Brazil. Brazilian Journal of Microbiology, v.37, p.533-537, 2006. Available from: <http://dx.doi.org/10.1590/S1517-83822006000400024>. Accessed: Nov. 15, 2014.
http://dx.doi.org/10.1590/S1517-83822006...
; QUINTELA et al., 2012QUINTELA, S. et al. Ochratoxin A in Spanish exportation wine market. Food Control, v.25, p.501-504, 2012. Available from: <http://dx.doi.org/10.1016/j.foodcont.2011.11.02>. Accessed: Dec. 15, 2014. doi:10.1016/j.foodcont.2011.11.02.
http://dx.doi.org/10.1016/j.foodcont.201...
; CAO et al., 2013CAO, J.L. et al. Moleculaly imprinted polymer-based solid phase clean-up for analysis of ochratoxin A in beer, red wine, and grape juice. Journal of Separation Science, v.36, p.1291-1297, 2013. Available from: <http://www.ncbi.nlm.nih.gov/pubmed/23471605>. Accessed: Dec. 20, 2014. doi: 10.1002/jssc.201201055.
http://www.ncbi.nlm.nih.gov/pubmed/23471...
; LASRAM et al., 2013LASRAM, S. et al. Occurrence of ochratoxin A in domestic beers and wines from Tunisia by immunoaffinity clean-up and liquid chromatography. Food Additives & Contaminants: Part B: Surveillance, v.6, p.1-5, 2013. Available from: <http://dx.doi.org/10.1080/19393210.2012.716453>. Accessed: Mar. 20, 2015. doi: 10.1080/19393210.2012.716453.
http://dx.doi.org/10.1080/19393210.2012....
).

Table 1:
Occurrence of ochratoxin A in grape juices in different countries.

The maceration of the grapes is the main processing step that contributes to the OTA contamination of juice and wine, since the contact of grape skin during this stage facilitates the migration of toxin to must (WELKE et al., 2009WELKE, J.E. et al. Aspectos relacionados à presença de fungos toxigênicos em uvas e ocratoxina A em vinhos. Ciência Rural, v.39, n.8, p.2567-2575, 2009. Available from: <http://dx.doi.org/10.1590/S0103-84782009005000201>. Accessed: Dec. 15, 2014. doi: 10.1590/S0103-84782009005000201.
http://dx.doi.org/10.1590/S0103-84782009...
). For this reason, in general, OTA levels are higher in red wines (in which maceration is necessarily done in contact with grape skin), followed by roses and whites wines (OTTENEDER & MAJERUS, 2000OTTENEDER, H.; MAJERUS, P. Occurrence of Ochratoxin A in wines and its geographical origin. Food Additives and contaminants, v.17, n.9, p.793-798, 2000. Available from: <http://dx.doi.org/10.1080/026520300415345>. Accessed: Nov. 20, 2014. doi: 10.1080/026520300415345.
http://dx.doi.org/10.1080/02652030041534...
; CABANES et al., 2002CABAÑES, F.J. et al. What is the source of ochratoxin A in wine? International Journal of Food Microbiology, v.79, p.213-215, 2002. Available from: <http://http://dx.doi.org/10.1016/S0168-1605(02)00087-9>. Accessed: Dec. 20, 2014. doi: 10.1016/S0168-1605(02)00087-9.
http://http://dx.doi.org/10.1016/S0168-1...
). BRERA et al. (2008BRERA, C. et al. Ochratoxin A contamination in Italian wine samples and evaluation of the exposure in the Italian population. Journal of Agricultural and Food Chemistry, v.56, p.10611-10618, 2008. Available from: <http://www.ncbi.nlm.nih.gov/pubmed/18939845>. Accessed: Dec. 15, 2014. doi: 10.1021/jf8016282.
http://www.ncbi.nlm.nih.gov/pubmed/18939...
) confirmed this fact analyzing 1166 samples of wines from different regions of Italy. The maximum values were 7.50ng mL-1for red, 4.07ng mL-1 for rosés, 1.95ng mL-1 for whites. In addition, the wines produced in the southern region of Italy had higher values of OTA compared to the north. The authors suggest that the difference of latitude (from 46.8°N to 36.8°S) and climate between the north and south regions may influence the OTA levels.

Special wines such as fortified or dessert wines have high sugar concentration, thus, the probability of fungal contamination, including ochratoxigenic fungi, is increased in these wines. The late harvest (when the grapes have excessive degree of ripeness) may be used to concentrate more sugar in grapes used in winemaking. An alternative to the production of these more sweet wines consists in interrupting the fermentation by fortification with grape wine distillate. This procedure also provides that the characteristic alcohol level of this beverage is achieved, since the fermentation was terminated. In this way, enological practices influence the concentration of OTA (PIETRI et al., 2001PIETRI, A. et al. Occurrence of Ochratoxin A in Italian wines. Food Additives and contaminants, v.17, n.7, p.647-654, 2001. Available from: <http://www.tandfonline.com/doi/abs/10.1080/02652030119480>. Accessed: Dec. 15, 2014. doi: 10.1080/02652030119480.
http://www.tandfonline.com/doi/abs/10.10...
; BELLI et al., 2004BELLI, N. et al. Ochratoxin A in wines, musts and grape juices from Spain. Journal of the Science of Food and Agriculture, v.84, n.6, p.591-594, 2004. Available from: <http://onlinelibrary.wiley.com/doi/10.1002/jsfa.1702/pdf>. Accessed: Nov. 15, 2014. doi: 10.1002/jsfa.1702.
http://onlinelibrary.wiley.com/doi/10.10...
; RATOLA et al., 2005RATOLA, N. el al. Evolution of ochratoxin A content from must to wine in Port Wine microvinification. Analytical and Bioanalytical Chemistry, v.382, p.405-411, 2005. Available from: <http://link.springer.com/article/10.1007%2Fs00216-005-3176-6>. Accessed: Dec. 15, 2014. doi: 10.1007/s00216-005-3176-6.
http://link.springer.com/article/10.1007...
; CHIODINI et al., 2006CHIODINI, A.M. et al. Ochratoxin A contents in wine: comparison of organically and conventionally produced products. Journal of Agricultural and Food Chemistry, v.54, p.7399-7404, 2006. Available from: <http://dx.doi.org/10.1021/jf0613482>. Accessed: Mar. 20, 2015. doi: 10.1021/jf0613482.
http://dx.doi.org/10.1021/jf0613482...
). VALERO et al. (2008VALERO, A. et al. Survey: ochratoxin A in European special wines. Food Chemistry, v.108, p.593-599, 2008. Available from: <http://dx.doi.org/10.1016/j.foodchem.2007.11.040>. Accessed: Dec. 15, 2014. doi: 10.1016/j.foodchem.2007.11.040.
http://dx.doi.org/10.1016/j.foodchem.200...
) found high levels of OTA in wines produced using grapes with excessive degree of ripeness (15.62ng ml-1)and fortified wines (27.79ng ml-1) elaborated with grape wine distillate.

Risk assessment related to OTA exposure through consumption of grape juice and wine

In 2001, The Joint FAO/WHO Expert Committee on Food Additives (JECFA) established a provisional tolerable weekly intake (PTWI) for OTA of 112ng kg-1 body weight (bw), which corresponds to approximately 16ng kg-1 pc per day (JECFA, 2007JECFA (2007). Joint FAO/WHO Expert Committee on Food Additives. Safety evaluations on certain mycotoxins in food. Available from: <http://www.inchem.org/documents/jecfa/jecmono/v47je01.htm>. Accessed: Nov. 15, 2014. .
http://www.inchem.org/documents/jecfa/je...
). The concept of provisional tolerable intake is based on the amount of a compound that can be consumed during the lifetime of an individual without causing damage to their health. In this way, the comparison of OTA exposure with PTWI may be used to evaluate the potential risks to human health. If the estimated exposure to the toxin is higher than PTWI there is a risk related to the consume of products containing OTA. The OTA estimated exposure through the consumption of grape juice and wine may be calculated according to the equation:

equation 1

where, EE: estimated exposure (ng kg-1 bw day-1), C: the consumption of juice and wine (mL day-1), OTA: OTA level (ng mL-1)and BW: body weight (60kg for adults and 20kg for children).

The OTA values found in grape juice (Table 1) and wine (Table 2) were used in calculation of estimated exposure to this toxin. Daily consumption of juice was estimated taking into consideration: (i) a cup (200mL) of grape juice consumed by children, since this beverage has been introduced in meals of public schools in the states of Rio Grande do Sul and Santa Catarina (RIO GRANDE DO SUL, 2009;RIO GRANDE DO SUL. Lei n. 13.247, de 08 de setembro de 2009. Inclui o suco de uva e o suco de laranja produzidos no Estado do Rio Grande do Sul no cardápio da merenda escolar da rede pública estadual de ensino. SANTA CATARINA, 2009SANTA CATARINA. Lei n. 14.995, de 16 de dezembro de 2009. Inclui na merenda escolar dos alunos da rede estadual de ensino, suco de uva produzido em Santa Catarina. Available from: <http://server03.pge.sc.gov.br/LegislacaoEstadual/2009/014995-011-0-2009-001.htm>. Accessed: Dec. 14, 2014.
http://server03.pge.sc.gov.br/Legislacao...
) and this amount has been daily consumed by children, (ii) 145mL of juice consumed by adults as established by the Consumer Expenditure Survey conducted by the Brazilian Institute of Geography and Statistics (IBGE, 2011IBGE (INSTITUTO BRASILEIRO DE GEOGRAFIA E ESTATÍSTICA). 2011. POF - Pesquisa de Orçamentos Familiares. Online. Available from: <http://www.ibge.gov.br/home/estatistica>. Accessed: Nov. 15, 2014.
http://www.ibge.gov.br/home/estatistica...
) and (iii) a glass of wine (150mL) per day recommended by some searches due to the presence of polyphenolic compounds.

Table 2:
Occurrence of ochratoxin A in wines produced in different places and evaluation of the estimated exposure to this mycotoxin.

The studies focused on the incidence of OTA in juices are incipient in relation to research on the occurrence of this toxin in wine. Levels of OTA ranged from <0.003 to 6.72ng mL-1 and 0.00003 to 27.79ng mL-1, for juice and wine, respectively. According to table 1, only a paper published in the literature (WOESE, 2000WOESE, K. Ochratoxin A in grape juice and wine. Mycotoxin Research, v.16, p.132-135, 2000. Available from: <http://dx.doi.org/10.1007/BF02943001>. Accessed: Dec. 15, 2014. doi: 10.1007/BF02943001.
http://dx.doi.org/10.1007/BF02943001...
) showed juice samples (marketed in Germany) with OTA levels above 2ng mL-1 (the maximum limit adopted by European and Brazilian law). Thus, the consumption of these grape juices represents a risk situation, since the estimated exposure to OTA (16.24 and 67.20ng kg-1bw day-1 for adults and children, respectively) was higher than the PTWI (16ng kg-1 bw day-1) defined as safe by JECFA.

OTA levels in juices were lower than 2ng mL-1 in other studies cited in table 1, in which the occurrence of this mycotoxin was evaluated, including samples from Brazil (ROSA et al., 2004ROSA, C.A.R. et al. Occurrence of ochratoxin A in wine and grape juice marketed in Rio de Janeiro, Brazil. Food Additives and Contaminants, v.21, p.358-364, 2004. Available from: <http://dx.doi.org/10.1080/02652030310001639549>. Accessed: Nov. 15, 2014. doi: 10.1080/02652030310001639549.
http://dx.doi.org/10.1080/02652030310001...
; SHUNDO et al., 2006SHUNDO, L. et al. Ochratoxin A in wines and grape juices commercialized in the city of São Paulo, Brazil. Brazilian Journal of Microbiology, v.37, p.533-537, 2006. Available from: <http://dx.doi.org/10.1590/S1517-83822006000400024>. Accessed: Nov. 15, 2014.
http://dx.doi.org/10.1590/S1517-83822006...
), China (CAO et al., 2013CAO, J.L. et al. Moleculaly imprinted polymer-based solid phase clean-up for analysis of ochratoxin A in beer, red wine, and grape juice. Journal of Separation Science, v.36, p.1291-1297, 2013. Available from: <http://www.ncbi.nlm.nih.gov/pubmed/23471605>. Accessed: Dec. 20, 2014. doi: 10.1002/jssc.201201055.
http://www.ncbi.nlm.nih.gov/pubmed/23471...
), Spain (BELLI et al., 2004BELLI, N. et al. Ochratoxin A in wines, musts and grape juices from Spain. Journal of the Science of Food and Agriculture, v.84, n.6, p.591-594, 2004. Available from: <http://onlinelibrary.wiley.com/doi/10.1002/jsfa.1702/pdf>. Accessed: Nov. 15, 2014. doi: 10.1002/jsfa.1702.
http://onlinelibrary.wiley.com/doi/10.10...
), Malaysia (LEE et al., 2012LEE, T.P. Molecularly imprinted polymer as sorbent in micro-solid phase extraction of ochratoxin A in coffee, grape juice and urine. Talanta, v.88, p.129-135, 2012. Available from: <http://www.sciencedirect.com/science/article/pii/S0039914011009210>. Accessed: Mar. 20, 2015. doi: 10.1016/j.talanta.2011.10.021.
http://www.sciencedirect.com/science/art...
) and Switzerland (ZIMMERLI & DICK, 1996ZIMMERLI, B.; DICK, R. Ochratoxin A in table wine and grape juice. Occurrence and risk assessment. Food Additives and contaminants, v.13, n.6, p.655-668, 1996. Available from: <http://dx.doi.org/10.1080/02652039609374451>. Accessed: Dec. 15, 2014. doi: 10.1080/02652039609374451.
http://dx.doi.org/10.1080/02652039609374...
). In these cases, the OTA exposure through consumption of juice has not represented a health risk, since the estimated exposure to this toxin were lower than the value established as PTWI by JECFA (ZIMMERLI & DICK, 1996ZIMMERLI, B.; DICK, R. Ochratoxin A in table wine and grape juice. Occurrence and risk assessment. Food Additives and contaminants, v.13, n.6, p.655-668, 1996. Available from: <http://dx.doi.org/10.1080/02652039609374451>. Accessed: Dec. 15, 2014. doi: 10.1080/02652039609374451.
http://dx.doi.org/10.1080/02652039609374...
; ROSA et al., 2004ROSA, C.A.R. et al. Occurrence of ochratoxin A in wine and grape juice marketed in Rio de Janeiro, Brazil. Food Additives and Contaminants, v.21, p.358-364, 2004. Available from: <http://dx.doi.org/10.1080/02652030310001639549>. Accessed: Nov. 15, 2014. doi: 10.1080/02652030310001639549.
http://dx.doi.org/10.1080/02652030310001...
; BELLI et al., 2004BELLI, N. et al. Ochratoxin A in wines, musts and grape juices from Spain. Journal of the Science of Food and Agriculture, v.84, n.6, p.591-594, 2004. Available from: <http://onlinelibrary.wiley.com/doi/10.1002/jsfa.1702/pdf>. Accessed: Nov. 15, 2014. doi: 10.1002/jsfa.1702.
http://onlinelibrary.wiley.com/doi/10.10...
; SHUNDO et al., 2006SHUNDO, L. et al. Ochratoxin A in wines and grape juices commercialized in the city of São Paulo, Brazil. Brazilian Journal of Microbiology, v.37, p.533-537, 2006. Available from: <http://dx.doi.org/10.1590/S1517-83822006000400024>. Accessed: Nov. 15, 2014.
http://dx.doi.org/10.1590/S1517-83822006...
; LEE et al., 2012LEE, T.P. Molecularly imprinted polymer as sorbent in micro-solid phase extraction of ochratoxin A in coffee, grape juice and urine. Talanta, v.88, p.129-135, 2012. Available from: <http://www.sciencedirect.com/science/article/pii/S0039914011009210>. Accessed: Mar. 20, 2015. doi: 10.1016/j.talanta.2011.10.021.
http://www.sciencedirect.com/science/art...
; CAO et al., 2013CAO, J.L. et al. Moleculaly imprinted polymer-based solid phase clean-up for analysis of ochratoxin A in beer, red wine, and grape juice. Journal of Separation Science, v.36, p.1291-1297, 2013. Available from: <http://www.ncbi.nlm.nih.gov/pubmed/23471605>. Accessed: Dec. 20, 2014. doi: 10.1002/jssc.201201055.
http://www.ncbi.nlm.nih.gov/pubmed/23471...
).

In wines (Table 2), VISCONTI et al. (1999VISCONTI, A. et al. Determination of ochratoxin A in wine by means of immunoaffinity column clean-up and high-performance liquid chromatography. Journal of Chromatography, v.864, p.89-101, 1999. Available from: <http://dx.doi.org/10.1016/S0021-9673(99)00996-6>. Accessed: Dec. 04, 2014. doi: 10.1016/S0021-9673(99)00996-6.
http://dx.doi.org/10.1016/S0021-9673(99)...
), VALERO et al. (2008VALERO, A. et al. Survey: ochratoxin A in European special wines. Food Chemistry, v.108, p.593-599, 2008. Available from: <http://dx.doi.org/10.1016/j.foodchem.2007.11.040>. Accessed: Dec. 15, 2014. doi: 10.1016/j.foodchem.2007.11.040.
http://dx.doi.org/10.1016/j.foodchem.200...
), BRERA et al. (2008BRERA, C. et al. Ochratoxin A contamination in Italian wine samples and evaluation of the exposure in the Italian population. Journal of Agricultural and Food Chemistry, v.56, p.10611-10618, 2008. Available from: <http://www.ncbi.nlm.nih.gov/pubmed/18939845>. Accessed: Dec. 15, 2014. doi: 10.1021/jf8016282.
http://www.ncbi.nlm.nih.gov/pubmed/18939...
) and ALTIOKKA et al. (2009ALTIOKKA, G. et al. Determination of Ochratoxin A in Turkish wines. Journal of Food and Drug Analysis, v.17, n.6, p.467-473, 2009. Available from: <http://www.fda.gov.tw/en/publishJFDAListContent.aspx?id=1641&chk=de5d0cc2-c810-40a7-8cf2-4e2482bb098a&param=pn%3D44%26cid%3D%26subcid%3D>. Accessed: Mar. 20, 2015.
http://www.fda.gov.tw/en/publishJFDAList...
) presented samples in which the OTA exposure was noteworthy. In the evaluation of wines from Turkey, for example, 70% of the samples had levels greater than 2ng mL-1 and exposure to OTA could reach 19.90ng kg-1 bw day-1 (ALTIOKKA et al., 2009ALTIOKKA, G. et al. Determination of Ochratoxin A in Turkish wines. Journal of Food and Drug Analysis, v.17, n.6, p.467-473, 2009. Available from: <http://www.fda.gov.tw/en/publishJFDAListContent.aspx?id=1641&chk=de5d0cc2-c810-40a7-8cf2-4e2482bb098a&param=pn%3D44%26cid%3D%26subcid%3D>. Accessed: Mar. 20, 2015.
http://www.fda.gov.tw/en/publishJFDAList...
). In Italian wines, similar estimated exposure (19,01 and 18,75ng kg-1 bw day-1) was observed by VISCONTI et al. (1999VISCONTI, A. et al. Determination of ochratoxin A in wine by means of immunoaffinity column clean-up and high-performance liquid chromatography. Journal of Chromatography, v.864, p.89-101, 1999. Available from: <http://dx.doi.org/10.1016/S0021-9673(99)00996-6>. Accessed: Dec. 04, 2014. doi: 10.1016/S0021-9673(99)00996-6.
http://dx.doi.org/10.1016/S0021-9673(99)...
) and BRERA et al. (2008BRERA, C. et al. Ochratoxin A contamination in Italian wine samples and evaluation of the exposure in the Italian population. Journal of Agricultural and Food Chemistry, v.56, p.10611-10618, 2008. Available from: <http://www.ncbi.nlm.nih.gov/pubmed/18939845>. Accessed: Dec. 15, 2014. doi: 10.1021/jf8016282.
http://www.ncbi.nlm.nih.gov/pubmed/18939...
), respectively. OTA was found in these wines in concentration exceeding 2ng mL-1 in 2.8% (VISCONTI et al., 1999VISCONTI, A. et al. Determination of ochratoxin A in wine by means of immunoaffinity column clean-up and high-performance liquid chromatography. Journal of Chromatography, v.864, p.89-101, 1999. Available from: <http://dx.doi.org/10.1016/S0021-9673(99)00996-6>. Accessed: Dec. 04, 2014. doi: 10.1016/S0021-9673(99)00996-6.
http://dx.doi.org/10.1016/S0021-9673(99)...
) and 87% (BRERA et al., 2008BRERA, C. et al. Ochratoxin A contamination in Italian wine samples and evaluation of the exposure in the Italian population. Journal of Agricultural and Food Chemistry, v.56, p.10611-10618, 2008. Available from: <http://www.ncbi.nlm.nih.gov/pubmed/18939845>. Accessed: Dec. 15, 2014. doi: 10.1021/jf8016282.
http://www.ncbi.nlm.nih.gov/pubmed/18939...
) of samples.

Considering data of table 2, the highest estimated exposure to OTA (69.50ng kg-1 bw day-1) was observed in special wines evaluated by VALERO et al. (2008VALERO, A. et al. Survey: ochratoxin A in European special wines. Food Chemistry, v.108, p.593-599, 2008. Available from: <http://dx.doi.org/10.1016/j.foodchem.2007.11.040>. Accessed: Dec. 15, 2014. doi: 10.1016/j.foodchem.2007.11.040.
http://dx.doi.org/10.1016/j.foodchem.200...
). In these wines, the OTA levels reached 27.79ng mL-1. The maximum limit established for OTA of 2ng mL-1 is not applied for special wines. In this type of wine, the fermentation step is stopped by the addition of a given amount of grape distilled as mentioned above. This procedure is performed in order to obtain sweeter wines, as part of sugars was not consumed by yeast when the fermentation is stopped. Results obtained by VALERO et al. (2008VALERO, A. et al. Survey: ochratoxin A in European special wines. Food Chemistry, v.108, p.593-599, 2008. Available from: <http://dx.doi.org/10.1016/j.foodchem.2007.11.040>. Accessed: Dec. 15, 2014. doi: 10.1016/j.foodchem.2007.11.040.
http://dx.doi.org/10.1016/j.foodchem.200...
) may indicate that fermentation is important role in the degradation of this mycotoxin.

Occurrence of OTA in wines at levels above 2ng mL-1 (Table 2) was observed in several countries including Brazil (WELKE et al., 2010WELKE, J.E. et al. Determination of Ochratoxin A in wine by high-performance thin-layer chromatography using charged coupled device. Journal Brazilian Chemical Society, v.21, p.441-446, 2010. Available from: <http://dx.doi.org/10.1590/S0103-50532010000300007>. Accessed: Dec. 15, 2014. doi: 10.1590/S0103-50532010000300007.
http://dx.doi.org/10.1590/S0103-50532010...
), China (ZHANG et al., 2013ZHANG, X. et al. Occurrence of Ochratoxin A in Chinese wines: influence of local meteorological parameters. European Food Research and Technology, v.236, p.277-283, 2013. Available from: <http://dx.doi.org/10.1007s00217-012-1886-5>. Accessed: Dec. 03, 2014. doi: 10.1007s00217-012-1886-5.
http://dx.doi.org/10.1007s00217-012-1886...
), Spain (BELLI et al., 2004BELLI, N. et al. Ochratoxin A in wines, musts and grape juices from Spain. Journal of the Science of Food and Agriculture, v.84, n.6, p.591-594, 2004. Available from: <http://onlinelibrary.wiley.com/doi/10.1002/jsfa.1702/pdf>. Accessed: Nov. 15, 2014. doi: 10.1002/jsfa.1702.
http://onlinelibrary.wiley.com/doi/10.10...
), Greece (SARIGIANNIS et al., 2014SARIGIANNIS, Y. et al. Ochratoxin A levels in Greek retail wines. Food Control, v.42, p.139-143, 2014. Available from: <http://www.sciencedirect.com/science/article/pii/S0956713514000620>. Accessed: Dec. 14, 2014. doi: 10.1002/jsfa.1300.
http://www.sciencedirect.com/science/art...
), Italy (VISCONTI et al., 1999VISCONTI, A. et al. Determination of ochratoxin A in wine by means of immunoaffinity column clean-up and high-performance liquid chromatography. Journal of Chromatography, v.864, p.89-101, 1999. Available from: <http://dx.doi.org/10.1016/S0021-9673(99)00996-6>. Accessed: Dec. 04, 2014. doi: 10.1016/S0021-9673(99)00996-6.
http://dx.doi.org/10.1016/S0021-9673(99)...
; BRERA et al., 2008BRERA, C. et al. Ochratoxin A contamination in Italian wine samples and evaluation of the exposure in the Italian population. Journal of Agricultural and Food Chemistry, v.56, p.10611-10618, 2008. Available from: <http://www.ncbi.nlm.nih.gov/pubmed/18939845>. Accessed: Dec. 15, 2014. doi: 10.1021/jf8016282.
http://www.ncbi.nlm.nih.gov/pubmed/18939...
; PRELLE et al., 2013PRELLE, A. et al. Comparison of clean-up methods for Ochratoxin A on wine, beer, roasted coffee and chili commercialized in Italy. Toxins, v.5, p.1827-1844, 2013. Available from: <http://dx.doi.org/10.3390/toxins5101827>. Accessed: Mar. 20, 2015. doi: 10.3390/toxins5101827.
http://dx.doi.org/10.3390/toxins5101827...
), Portugal (PEN et al., 2010), Russia (RUSANOVA et al., 2009RUSANOVA, T.Y. et al. Non-instrumental immunochemical tests for rapid ochratoxin A detection in red wine. Analytica Chimica Acta, v.653, p.97-102, 2009. Available from: <http://dx.doi.org/10.1016/j.aca.2009.08.036>. Accessed: Dec. 15, 2014. doi: 10.1016/j.aca.2009.08.036.
http://dx.doi.org/10.1016/j.aca.2009.08....
) and Turkey (ALTIOKKA et al., 2009ALTIOKKA, G. et al. Determination of Ochratoxin A in Turkish wines. Journal of Food and Drug Analysis, v.17, n.6, p.467-473, 2009. Available from: <http://www.fda.gov.tw/en/publishJFDAListContent.aspx?id=1641&chk=de5d0cc2-c810-40a7-8cf2-4e2482bb098a&param=pn%3D44%26cid%3D%26subcid%3D>. Accessed: Mar. 20, 2015.
http://www.fda.gov.tw/en/publishJFDAList...
). These results demonstrate that the OTA exposure through wine consumption may be a concern at these countries. In addition, samples containing high levels of OTA were detected in Italy (BRERA et al., 2008BRERA, C. et al. Ochratoxin A contamination in Italian wine samples and evaluation of the exposure in the Italian population. Journal of Agricultural and Food Chemistry, v.56, p.10611-10618, 2008. Available from: <http://www.ncbi.nlm.nih.gov/pubmed/18939845>. Accessed: Dec. 15, 2014. doi: 10.1021/jf8016282.
http://www.ncbi.nlm.nih.gov/pubmed/18939...
), Turkey (ALTIOKKA et al., 2009ALTIOKKA, G. et al. Determination of Ochratoxin A in Turkish wines. Journal of Food and Drug Analysis, v.17, n.6, p.467-473, 2009. Available from: <http://www.fda.gov.tw/en/publishJFDAListContent.aspx?id=1641&chk=de5d0cc2-c810-40a7-8cf2-4e2482bb098a&param=pn%3D44%26cid%3D%26subcid%3D>. Accessed: Mar. 20, 2015.
http://www.fda.gov.tw/en/publishJFDAList...
) and China (ZHANG et al., 2013ZHANG, X. et al. Occurrence of Ochratoxin A in Chinese wines: influence of local meteorological parameters. European Food Research and Technology, v.236, p.277-283, 2013. Available from: <http://dx.doi.org/10.1007s00217-012-1886-5>. Accessed: Dec. 03, 2014. doi: 10.1007s00217-012-1886-5.
http://dx.doi.org/10.1007s00217-012-1886...
), where the occurrence of OTA was verified in 95%, 85% and 57% of the samples, respectively. In other studies, despite the OTA has been found in wines from Africa (REMIRO et al., 2013REMIRO, R. et al. Levels of ochratoxins in Mediterranean red wines. Food Control, v.32, p.63-68, 2013. Available from: <http://dx.doi.org/10.1016/j.foodcont.2012.11.040.>. Accessed: Nov. 15, 2014. doi: 10.1016/j.foodcont.2012.11.040.
http://dx.doi.org/10.1016/j.foodcont.201...
), Spain (CHIODINI et al., 2006CHIODINI, A.M. et al. Ochratoxin A contents in wine: comparison of organically and conventionally produced products. Journal of Agricultural and Food Chemistry, v.54, p.7399-7404, 2006. Available from: <http://dx.doi.org/10.1021/jf0613482>. Accessed: Mar. 20, 2015. doi: 10.1021/jf0613482.
http://dx.doi.org/10.1021/jf0613482...
) and Israel (REMIRO et al., 2013REMIRO, R. et al. Levels of ochratoxins in Mediterranean red wines. Food Control, v.32, p.63-68, 2013. Available from: <http://dx.doi.org/10.1016/j.foodcont.2012.11.040.>. Accessed: Nov. 15, 2014. doi: 10.1016/j.foodcont.2012.11.040.
http://dx.doi.org/10.1016/j.foodcont.201...
) at low levels (0.0844 to 0.455, 0.007 to 0.009 and 0.003 to 0.0654, respectively), this toxin was found in 100% of the samples produced in these countries. In these cases, the amount and frequency of wine consumption can be determining factors for exposure to OTA pose a risk to health.

CONCLUSION:

The OTA is present in several countries as a contaminant in grapes, juice and wine. In Europe, several studies have been conducted in order to map the areas where the development of mycotoxigenic fungi is more favorable, and consequently the production of OTA. In Brazil, these studies are still incipient.

A. niger and A. carbonarius are mainly responsible for the fungic contamination of grapes. Moreover, these fungal species should be highlighted both for its high incidence and as for its great capacity to produce OTA. Factors that influence the OTA levels in juices and wines are well established in the literature. The grape variety used in winemaking, the presence of physical damage in surface of grapes and climatic conditions are frequently related to occurrence of OTA.

The estimation of OTA exposure through the consumption of juice and wine revealed that few studies showed samples in which the consumption could pose health risk. The estimated exposure to OTA was higher than the tolerable intake for this mycotoxin in rare cases. However, the frequency of occurrence of OTA was high. In addition, in some cases, the number of samples with OTA levels above the maximum limit established was significant in some countries.

Although the evaluations published in literature indicate that the OTA exposure through the consume of grape juice and wine poses risk to health in few cases, only the periodic survey on the levels of this toxin may ensure the security related to the consume of these products. The incidence of OTA in juices and wines must be constantly monitored due to the following factors: (i) toxic effects of OTA, (ii) evaluation of a reduced number of samples produced in Brazil, (iii) recent publication of Brazilian legislation establishing maximum limits for this mycotoxin, (iv) introduction of the grape juice in school meals and recommendation of regular intake of wine because of its functional properties.

ACKNOWLEDGEMENTS

The authors thank Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (FAPERGS) and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for financial support and scholarships.

Publication Dates

  • Publication in this collection
    25 Aug 2015
  • Date of issue
    Jan 2016

History

  • Received
    25 Nov 2014
  • Accepted
    12 May 2015
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