Tainan, Nov. 17 (CNA) A research team from National Cheng Kung University's (成功大學) College of Medicine said Monday it has gained insight into how exposure to industrial plasticizers can lead to low testosterone levels and possibly infertility in males.
Professor Lee Ching-chang (李俊璋) of the school's Department of Environmental and Occupational Health and his research team based their findings on a study of 259 infertile men recruited through infertility clinics in Taiwan and 39 fertile men recruited from childbirth preparatory classes between 2011 and 2014.
The participants' urinary concentrations of plasticizers were measured and indicators of testicular function were compared to test the link between the industrial chemicals and infertility and learn how the mechanism works.
At a press briefing at the university on Monday, Lee said the study found that the concentration of plasticizers in the system of an infertile male was more than double that of a fertile male.
That was the case, Lee said, because plasticizers in a male's system can affect the functioning of Leydig cells and suppress the production of testosterone.
When both the Leydig cell hormones' insulin-like peptide 3 (INSL3) and testosterone were low, males were likely to have poor semen quality, he said.
Industrial plasticizers, also known as phthalates, are additives that make plastics (especially PVC) used in a wide range of commercial applications more flexible and harder to break, and have been suspected of having negative effects on reproductive systems.
The team said people are now often frequently exposed to plasticizers, including from hot or cold food and drinks contained in bags or boxes containing plasticizers.
Males who used more bath wash, shampoo, shaving cream and colognes were also found to have higher concentrations of plasticizers in their systems, Lee said.
Lee said the team's study was published in Human Reproduction, a journal of medicine and health put out by the Oxford University Press, in its most recent issue.
(By S.J. Yang and Lillian Lin)enditem/ls