Lack of effect on rat testicular organogenesis after in utero exposure to 3-monochloropropane-1,2-diol (3-MCPD)

3-Monochloropropane-1, 2-diol causes irreversible damage to reproductive ability independent of hormone changes in adult male rats

3-MCPD, a contaminant frequently detected in foodstuffs, has been reported to damage human kidneys and testes. Previous studies can be used to evaluate the risk to humans of exposure to excessive 3-MCPD for a short period. However, the effects of withdrawal after 3-MCPD exposure have rarely been studied. Adult male SD rats were orally administered 0, 36 and 72 mg 3-MCPD/kg b.w./day for 4 weeks, followed by a 7-week recovery period. 3-MCPD significantly reduced RBC, HGB and HCT levels, indicating a phenotype of anemia, which returned to normal after the recovery period. 3-MCPD induced dysfunction in the liver and kidneys, which were characterized by hepatomegaly and elevated serum ALT, TBIL levels, and nephromegaly and elevated serum urea, UA contents. These effects were also restored to normal after the recovery period. Although the abnormal levels of testosterone and progesterone returned to normal, 3-MCPD-induced atrophy in testes, decreased sperm concentration and motility, and an increased rate of teratosperm still existed after the recovery period. 3-MCPD can induce restorable anemia and dysfunction in liver and kidney but irreversibly damage the reproductive system with normal sex hormone levels. This study may provide a novel perspective for characterizing the ongoing risk of exposure to 3-MCPD.

Update of the risk assessment on 3-monochloropropane diol and its fatty acid esters

The CONTAM Panel updated the assessment of the risks for human health related to the presence of 3-monochloropropane diol (3-MCPD) and its fatty acid esters in food published in 2016 in view of the scientific divergence identified in the establishment of the tolerable daily intake (TDI) in the Joint FAO/WHO Expert Committee on Food Additives and Contaminants (FAO/WHO) report published in 2017. In this update, dose-response analysis was performed following the recent EFSA Scientific Committee guidance on the use of benchmark dose (BMD) approach in risk assessment, and a review of available data on developmental and reproduction toxicity was included. The outcome of this review indicates that in rats short-term exposure to 3-MCPD above 1 mg/kg body weight (bw) per day can induce reduced sperm motility associated with reduced male fecundity. Decreased sperm count and histopathological changes in the testis and epididymis were observed following longer treatment periods at higher doses. Regarding increased incidence kidney tubular hyperplasia, BMD analysis using model averaging resulted in a BMDL 10 of 0.20 mg/kg bw per day in male rats, which was selected as the new Reference Point (RP) for renal effects. For the effects on male fertility, decreased sperm motility was selected as the most sensitive relevant endpoint and a BMDL 05 of 0.44 mg/kg bw per day was calculated. The RP for renal effects was considered to derive an updated group TDI of 2 μg/kg bw per day for 3-MCPD and its fatty acid esters and was considered protective also for effects on male fertility. The established TDI of 2 μg/kg bw per day is not exceeded in the adult population. A slight exceedance of the TDI was observed in the high consumers of the younger age groups and in particular for the scenarios on infants receiving formula only.

Direct determination of 3-chloro-1,2-propanediol esters in beef flavoring products by ultra-performance liquid chromatography tandem quadrupole mass spectrometry

A sensitive UPLC-TQ-MS method coupled with amino solid-phase extraction was developed for direct determination of 3-MCPD esters in the natural beef flavoring products. This method was evaluated in terms of linearity, repeatability and sensitivity.