Research into falling sperm counts finds ‘alarming’ levels of chemicals in male urine samples

Scientists searching for the causes of falling sperm counts are getting a clearer picture of the role played by chemical pollutants - and it’s not a pretty one.

A study of urine samples from nearly 100 male volunteers has uncovered “alarming” levels of endocrine disruptors known to reduce human fertility.

Cocktails of chemicals such as bisphenols and dioxins, which are believed to interfere with hormones and affect sperm quality, were present at levels up to 100 times those considered safe.

The median exposure to these chemicals was 17 times the levels deemed acceptable.

“Our mixture risk assessment of chemicals which affect male reproductive health reveals alarming exceedances of acceptable combined exposures,” wrote the authors of the study, published on Thursday in the journal Environment International.

The study measured nine chemicals, including bisphenol, phthalates and paracetamol, in urine samples from 98 Danish men aged 18 to 30.

Additionally, it used existing data, mostly from the European Food Standards Agency (EFSA), to estimate their likely exposure to 20 other chemicals.

The team then compared the results with acceptable levels of exposure derived from the scientific literature.

This resulted in a measure of the potential impact of each chemical, which the scientists combined to produce an overall risk measure - or “hazard index” - for the cocktail of compounds.

The study authors, led by Professor Andreas Kortenkamp of Brunel University London, said they were “astonished” by the magnitude of this hazard index in the volunteers studied.

They were also surprised to find that bisphenol A (BPA) was the dominant risk factor, given that recent research had focused on phthalates, which are used in plastics.

BPA was followed