Pesticide residues and estrogenic activity in fruit and vegetables sampled from major fresh produce markets in South Africa

ABSTRACT

Food is likely to be one of the major pathways through which people are exposed to endocrine-disrupting chemicals. With the exception of residual effects, there are concerns that a number of naturally occurring and synthetic chemicals exert adverse effects upon endocrine systems in wildlife and humans. The current study reports selected pesticide concentrations and the total estrogenic activity of fruit and vegetables using the recombinant yeast oestrogen screen (YES) and T47D-KBluc reporter gene assays. A total of 53 food samples (27 fruit and 26 vegetables) from Johannesburg and Tshwane fresh produce markets (in South Africa) were analysed. Of these, 17 contained one to three different pesticide residues with concentrations ranging between 0.01 and 0.68 mg kg^–1, whereas in the rest of the samples no residues were detected. All pesticides detected except in one sample were below the maximum residue level (MRL), but others were unauthorised for use in specified fruit and vegetables. Estrogenic activity was detected in 26.4% (14 samples) of the samples tested, and the estradiol equivalents ranged from 0.007 to 2 pg g^–1. Although the estrogenic activity was low, it may contribute to adverse health effects. Continuous monitoring for pesticides in fruit and vegetables is important in view of the unauthorised pesticides detected in produce from South Africa and the endocrine-disrupting chemical activity found.

KEYWORDS:

• Fresh produce
• agricultural chemicals
• estrogenic activity
• endocrine-disrupting chemicals
• yeast oestrogen screen
• T47D-KBluc

Acknowledgements

The authors gratefully acknowledge editorial input from Ms Barbara English.

Additional information

Funding

The authors acknowledge the South African Table Grape Industry, the University of Pretoria, Institute of Food Nutrition and Well-Being as well as the Department of Science and Technology sponsored and National Research Foundation administered Centre of Excellence in Food Security (Project No 140701).