As the incidence of any condition becomes more common, invariably it becomes easierto ignore. Infertility is one such area where the glaring statistic is matched to the other extreme by our complacency (1 in 6 couples are infertile). Those wanting answers need look no further than the story that the animal kingdom has to tell.

It wasn’t so long ago that alarm bells were ringing in the corridors of governments.  In the 1970s, DDT and PCBs became restricted following the ecological disaster on wildlife exposed to these chemicals. We were comforted when we stopped seeing the gross birth deformities, the enlarged thyroid glands, the wasting syndromes, the abnormal sex glands and the immune deficiency disorders that were wiping out colonies of birds and marine life. But there were more insidious, invisible problems. New chemicals, deemed to have less toxic side-effects, were unleashed on the global community - and we are now just beginning to reap the consequences.

Nowadays, the adverse effects of chemicals on animal species doesn’t often hit the headlines, but there was a worrying UK report, released in March 2002, which linked high levels of oestrogenic chemicals to feminization in 50% of male fish in lowland English rivers. A proportion of these “intersex” fish had developed eggs in their testes, some had female reproductive tracts, 10% were completely sterile, and a further 25% had damaged sperm.¹   The contamination was traced back to water pumped from sewage treatment plants into the rivers. High levels of ethinyl oestradiol (an active ingredient of the contraceptive pill) were blamed, but there were also high levels of oestrogenic compounds derived from the bacterial breakdown of detergents and personal care products in these treatment plants.  As metropolitan areas tend to depend upon recycled or treated water for their drinking supply, such contamination raises serious concern.

Implications for human development

Establishing hard evidence on changes in human sexual development is difficult, and not within the interests of the agrichemical industry to fund such studies. As regulatory bodies continue to ignore animal studies, we can only assume they’ve adopted a wait-and-see approach. But the longer generational span of humans means that we may not know the true effects for 30 years.

However, one human experiment proved the effects of synthetic oestrogen on unborn children. The prescription drug DES (diethylstilbestrol) was promoted in the 1940s-1960s to prevent miscarriage and help produce bigger, stronger babies, but it was banned when contradictory evidence started to accumulate. It was found that synthetic oestrogen exerts its effects within the first few weeks of gestation and substantially interferes with the programming of sexual development; once this occurs the damage is irreversible. Both male and female babies were affected: in the males there were genital defects, undescended testicles, the development of one testicle and one ovary (hermaphrodite), small penises and abnormal sperm; in females there were reproductive tract deformities and a rare form of vaginal cancer.

What other evidence do we have? There has been a marked decrease in fertility in both sexes since 1938, including an overall 45% reduction in sperm count and an increase in sperm abnormalities. Defects in the reproductive organs of male babies (i.e. failure of normal descent of the testis, abnormal position of the opening of the urethra) are becoming more common.² Furthermore, it is estimated that 20% of women now suffer endometriosis and around 10% of women have PCOS (polycystic ovarian syndrome) – both conditions leading to infertility. Countries such as Thailand are witnessing the feminization of males; they have the physical appearance of females, but also have small penises. 

You could dismiss some of these abnormalities as freaks of nature; but once you understand how vulnerable sexual development is in a chemically disturbed environment, this evidence takes on a new light.

At conception the fertilized egg is essentially female.  However, the male has a testosterone surge during the seventh week of gestation that signals the sex glands to differentiate into testicles. Then the testicles secrete testosterone which programs the development of the penis, prostate and scrotum. But minute amounts of endocrine disruptive chemicals can either inhibit this testosterone surge or prevent testosterone from acting at the target tissues. The end-result is risk of feminization and the failure of the sex glands to fully mature.

Which chemicals are to blame?

·        Synthetic oestrogenic chemicals, which oppose the testosterone surge, as is already occurring in our marine life. These chemicals are bio-accumulative. We ingest them through our drinking water (treated and rain water), the food we eat, and the air we breathe (from aerial crop spraying). They are found in:

o        pesticides like DDT, DDE, Dieldrin, Lindane, Chlordane, Aldrin, Heptachlor (so you need to be careful about the country of origin of the food you buy):

o        plastics and polystyrene, from which they leach;

o        detergents and personal care products and their breakdown products

·        Phthalates, used to increase plastic flexibility and found in children’s toys, vinyl, nail polish, and used as a fixative for perfume, deodorants and hair spray. These chemicals inhibit testosterone production. Their adverse effect on the differentiation of male foetuses was proved only 4 years ago ³

·        Anti-androgens, which inhibit or block testosterone activity. They are found in pesticides and fungicides.

^·             Chemicals that alter the body’s metabolism of naturally produced hormones. One example is the pesticide Atrazine, which switches on aromatase enzymes which convert testosterone to oestrogen and studies have shown that this chemical is responsible for the feminization in frogs in the USA. ⁴

What can we do?

I always believe that the consumer has the last say. If we buy organically produced food, we increase the demand. As more farmers go organic, so there will be less pollution. Water quality will improve -but in the meantime, use a good distillation or reverse osmosis unit. Use only natural beauty care products and perfumes, and be very discriminating about laundry and dishwashing products. Don’t use pesticides or weed killers in your home or garden, and try to get by without polystyrene and plastic bags/food containers.

1. www.brunel.ac.uk/depts/bio/info/intersex.htm

2. www.agius.com/hew/resource/endodis.htm

3. www.nottoopretty.org/    

    http://www.phthalates.org/whatare/index.asp

4. http://eces.org/archive/ec/pollution/pesticides.shtml