Diphenyl Phosphate Test

Diphenyl phosphate is a urinary metabolite formed after exposure to triphenyl phosphate, a flame retardant used in furniture foam, electronics, textiles, and some personal care products such as nail polish and cosmetics. Exposure occurs through inhalation of household dust, skin contact, and ingestion from contaminated food or packaging materials.

Triphenyl phosphate and its metabolites are endocrine disruptors that interfere with hormone signaling, particularly thyroid and reproductive hormones. Thyroid hormones regulate metabolic rate, lipid metabolism, and cardiovascular function, making disruption relevant to long term metabolic health. Human studies have linked exposure to altered thyroid hormone levels, reduced semen quality, and changes in reproductive hormone balance.

Metabolism of triphenyl phosphate occurs primarily in the liver through cytochrome P450 enzymes, producing diphenyl phosphate as a major excreted metabolite. Elevated urinary levels indicate ongoing exposure and detoxification demand. Experimental data also suggest interactions with receptors involved in fat cell development, raising concern for metabolic effects.

That said, because flame retardants are ubiquitous in indoor environments, exposure is often chronic and underrecognized. Measuring diphenyl phosphate helps identify a hidden contributor to endocrine and metabolic strain.