Insecticides in human breast milk.

Area of Science:

• Environmental Science
• Toxicology
• Human Health

Background:

• Persistent organic pollutants (POPs) are a global health concern.
• Human breast milk can be a route of exposure to environmental contaminants.
• Previous Norwegian studies focused primarily on DDT levels.

Purpose of the Study:

• To quantify levels of specific organochlorine pesticides in human breast milk.
• To assess the variation of pesticide concentrations based on lactation stage and season.
• To compare current DDT levels with historical data.

Main Methods:

• Analysis of 50 human breast milk samples using gas chromatography and thin-layer chromatography.
• Quantification of DDT, hexachlorobenzene, benzene-hexachlorides, dieldrin, aldrin, and heptachlorepoxide.
• Comparison of detected levels with WHO recommended maximums for cow milk.

Main Results:

• DDT, hexachlorobenzene, and benzene-hexachlorides were detected in all samples.
• Levels of these three pesticides frequently exceeded WHO maximums for cow milk.
• Insecticide concentrations were highest in colostrum and decreased over lactation.
• Seasonal variations showed higher contamination in May/June compared to April.
• No significant change in mean DDT concentration was observed over five years.

Conclusions:

• Human breast milk in Norway is contaminated with multiple organochlorine pesticides.
• Lactation stage and season significantly influence pesticide levels.
• Findings highlight the need for ongoing monitoring of environmental contaminants in breast milk.