Benzene is recognized by the IARC (International Agency for Research on Cancer) as carcinogenic to humans. Everybody knows what the maximum acceptable concentration of benzene in water is according to the World Health Organization. It's 10 μg/L. But what about pickes?
Pickled cucumbers stored in plastic bottles may have 44.7 μg/L of benzene after 67 weeks, while pickled cucumbers stored in glass bottles only 5.2 μg/L after 27 weeks. Roughly 99% of the benzene present in the human body was inhaled. So, how does it get into pickle jars? Turns out it doesn't get there, but is formed through a chemical reaction when benzoate reacts with ascorbic acid and transition metals such as copper and iron and can be accelerated by light and heat. Benzoate and ascorbic acid are widely used as preservatives and antioxidants, respectively, in nonalcoholic beverages. Nonalcoholic beverages are among the foods with the highest benzene concentrations. The amount of benzene found in other foods by qualitative and quantitative studies is small.
FYI: The lethal oral dose of benzene for humans is 125 mg/kg.
- Benzene as a Chemical Hazard in Processed Foods. Int J Food Sci. 2015; 2015: 545640.