Exposure of human fetal testes (obtained with ethical permission from legal pregnancy terminations) to the same high phthalate levels as in rats has no effect on their testosterone production. To induce this effect, pregnant rats have to be exposed to phthalate levels 50,000 times higher than pregnant women are exposed to. Phthalates cause male reproductive disorders in rats by reducing production of the male sex hormone – testosterone – by the testes of the male fetus. More importantly, other evidence points in the completely opposite direction. The problem is that this approach can never prove that the exposure caused the disorder. Some, but not all, such studies have shown an association between male reproductive disorders and phthalate exposure of the mother. The seemingly direct way to answer this question is to measure phthalate exposure of pregnant women and see if high exposure is associated with reproductive disorders in their sons.
The most widely used plasticisers are called phthalates, which come in different forms with different uses. As a guide, the more flexible the plastic, the more plasticiser it will contain. Plasticisers are chemicals used to make plastic (which is naturally hard and brittle) bendy and resistant to breaking, so prolonging its useful life. After all, we don’t eat the plastic wraps around food or chew electric wiring. Most people probably don’t understand how we are exposed to chemicals from plastics. This means we don’t really have an unexposed group (“control”) against which to compare. Plastics bring everyday benefits whether through children’s toys, the insulation around electrical wiring, their utility in food containers/wraps or their widespread use in medical products from blood bags, gloves and syringes, to the coating of some tablets and capsules.īut are there hidden dangers of plastics to human health, especially to male fertility? This is a surprisingly difficult question to answer, not least because everyone is exposed to chemicals that derive from plastics.
Without their thousands of uses, many of which are not obvious to us, our modern world could not function as it is. Plastics are part of the fabric of our everyday lives and perform many essential functions. But whether plastics are to blame isn’t a simple matter. I share the concerns about the high prevalence of low sperm counts (one in six young men) – and my research is directed at trying to identify what causes it.
Recent research has reignited concerns that exposure to chemicals from plastics might be to blame for low sperm counts in young men.
0 kommentar(er)
