Men with higher exposure to diethylhexyl phthalate (DEHP), one of the phthalates, which is an umbrella term for a group of substances based on phthalic acid, have lower sperm motility and may therefore experience more difficulties conceiving children, according to a new paper.

Many phthalates are found in soft plastics in our daily surroundings: wallpaper, sandals, nail polish, perfume, floors, carpets and more. Some suspect  phthalates may be endocrine disruptors and since phthalate molecules leak out of plastics, we are exposed to it daily and absorb the chemicals through food, drink, skin contact and inhalation. Phthalate levels can be measured by a simple urine sample.  

The team studied metabolite levels of DEHP in urine as an indicator of exposure, as well as the semen quality of 300 men between the ages of 18 and 20. The results show that the higher metabolite levels the men had, the lower their sperm motility. For one quarter of the men with the lowest levels of exposure, 57 percent of the sperm cells were moving forward, compared to 46 percent for the quarter of the men with the highest levels of exposure. Previous research has reported that there is a linear connection also between sperm motility and chances of becoming pregnant, the findings could indicate that the more exposed one is to DEHP, the smaller the chances are of having children. 

“There are other studies that support our findings with regard to the link between DEHP metabolites and sperm motility, but also studies that have not found any connection. Moreover, the substances break down in the body within a few days, so there is no cause for immediate concern. However, we should be aware that there may be a problem and that it can be an important issue for further research,” says Jonatan Axelsson, researcher at the Department of Laboratory Medicine, Lund University. 

DEHP is already on the EU’s list of substances with particularly hazardous properties, and since earlier this year, you need special authorization to use substances when manufacturing goods and chemical products.

Citation: Jonatan Axelssona, Lars Rylander, Anna Rignell-Hydbom, Bo A.G. Jönsson, Christian H. Lindh, Aleksander Giwercman, "Phthalate exposure and reproductive parameters in young men from the general Swedish population", Environment International Volume 85, December 2015, Pages 54–60 doi:10.1016/j.envint.2015.07.005