Glazed clay pottery and lead exposure in Mexico: Current experimental evidence

Nutr Neurosci. 2017 Nov;20(9):513-518. doi: 10.1080/1028415X.2016.1193967. Epub 2016 Jun 14.

Abstract

Objectives: Lead exposure remains a significant environmental problem; lead is neurotoxic, especially in developing humans. In Mexico, lead in human blood is still a concern. Historically, much of the lead exposure is attributed to the use of handcrafted clay pottery for cooking, storing and serving food. However, experimental cause-and-effect demonstration is lacking. The present study explores this issue with a prospective experimental approach.

Methods: We used handcrafted clay containers to prepare and store lemonade, which was supplied as drinking water to pregnant rats throughout the gestational period.

Results and discussion: We found that clay pots, jars, and mugs leached on average 200 µg/l lead, and exposure to the lemonade resulted in 2.5 µg/dl of lead in the pregnant rats' blood. Neonates also showed increased lead content in the hippocampus and cerebellum. Caspase-3 activity was found to be statistically increased in the hippocampus in prenatally exposed neonates, suggesting increased apoptosis in that brain region. Glazed ceramics are still an important source of lead exposure in Mexico, and our results confirm that pregnancy is a vulnerable period for brain development.

Keywords: Apoptosis; Glazed ceramics; Hippocampus; Lead exposure; Prenatal.

MeSH terms

  • Aluminum Silicates / chemistry*
  • Animals
  • Animals, Newborn
  • Behavior, Animal / drug effects
  • Cerebellum / drug effects
  • Cerebellum / metabolism
  • Citrus / chemistry
  • Clay
  • Cooking and Eating Utensils*
  • Dietary Exposure / adverse effects*
  • Female
  • Food Contamination*
  • Food Storage / instrumentation*
  • Fruit and Vegetable Juices / adverse effects
  • Hippocampus / drug effects
  • Hippocampus / metabolism
  • Humans
  • Lead / blood
  • Lead / metabolism
  • Lead / toxicity*
  • Lead Poisoning, Nervous System / blood
  • Lead Poisoning, Nervous System / etiology*
  • Male
  • Maternal Exposure / adverse effects
  • Mexico
  • Pregnancy
  • Random Allocation
  • Rats, Wistar
  • Tissue Distribution
  • Toxicokinetics

Substances

  • Aluminum Silicates
  • Lead
  • Clay