Exposure of neonates to ochratoxin A: first biomonitoring results in human milk (colostrum) from Chile

Abstract

The mycotoxin ochratoxin A (OTA) and its metabolite ochratoxin alpha (OTα) were determined in milk and blood from nine lactating women who provided samples soon after delivery at a hospital in southern Chile. The analytical method applied liquid-liquid extraction with chloroform, and in the case of blood, an extra purification with solid phase extraction prior to HPLC analysis with fluorescence detection. OTA was detected in all human milk samples, with an average concentration of 106 ± 45 ng/L (range 44-184 ng/L). Levels of OTα were 40 ± 30 ng/L (LOQ 40 ng/L), but increased considerably upon enzymatic hydrolysis with ß-glucuronidase/sulfatase (up to 840 ± 256 ng/L) in human milk. By contrast, there was no evidence for conjugates of OTA. The data on OTA in breast milk and levels reported in blood from women in Chile are indicative of an efficient lactational transfer of the mycotoxin. Infant exposure to OTA was estimated by considering their daily OTA intake with human milk at early stages of nursing. For the majority of milk samples, the calculated OTA intake of infants exceeded the tolerable daily intake (TDI) of 5 ng/kg body weight (bw)/day proposed by the Nordic Expert Group, and infant exposure approached the provisional tolerable doses of 14-16 ng/kg bw/day suggested by the Joint FAO/WHO Expert Committee on Food Additives (JEFCA) and by EFSA for adults. The present study documents and confirms the presence of OTA in human milk at levels where the TDI can be exceeded. These results point out the need to continue food and biological monitoring and to develop strategies, e.g. dietary recommendations to pregnant and lactating women, aimed to reduce OTA exposure in early periods of life.

Prevalence of Ochratoxin A in Human Milk in the Khorrambid Town, Fars Province, South of Iran

“…The result of a similar study in Egypt indicated that from a total 120 human milk samples, OTA was found in 43 (35.8%) of the samples (22). In addition, the mean concentration of the toxin in this study was higher than that of the previous studies, such as 17.5 ng/L in Brazil (12), 10-57 ng/L in Italy (23,24), and 17-30 ng/L in Germany (16), while lower amounts such 8.87 ng/L was noticed in Egypt (25), 106 ng/L in Chile (26), 39.8 ng/L in Norway (27), and 7900 ng/L in Sierra Leone (28). …”

A Review of the Diagnosis and Treatment of Ochratoxin A Inhalational Exposure Associated with Human Illness and Kidney Disease including Focal Segmental Glomerulosclerosis

“…For example, rat neonates exposed to OTA in only lactational milk had a 4 to 5 times higher level of OTA compared with those rats exposed only via the placenta [60]. Results of a recent biomonitoring study in Chile confirmed the presence of OTA in breast milk at levels such that the tolerable daily intake could be exceeded [75]. Of concern, in 50 lactating mothers and their infants in Egypt, the presence of OTA was associated with significantly higher levels of urine microglobulin and microalbuminuria in the infants consistent with early renal injury [76].…”

“…Antioxidants, including glutathione, are also likely to be helpful for their antioxidant and detoxification effects [23]. Vitamins A, C, E and selenium are other potentially beneficial antioxidants that may be protective in their role as superoxide anion scavengers [22, 75]. …”

Ochratoxin A: Developmental and Reproductive Toxicity—An Overview

“…The fetal and neonatal exposure to OTA is likely determined by the analysis of cord blood samples from pregnant women, human blood, colostrum, milk, and urine (Micco et al, 1991;Kovacs et al, 1995;Miraglia et al, 1998;Skaug et al, 1998;Muñoz et al, 2010;Klapec et al, 2012). The fetal and neonatal exposure to OTA is likely determined by the analysis of cord blood samples from pregnant women, human blood, colostrum, milk, and urine (Micco et al, 1991;Kovacs et al, 1995;Miraglia et al, 1998;Skaug et al, 1998;Muñoz et al, 2010;Klapec et al, 2012).…”