Feb 20 2008
According to the latest research exposure to environmental toxins can damage sperm and the resulting defects can be passed down for generations.
Scientists say tests on rats showed sperm damage caused by exposure to garden chemicals remained up to four generations later.
Their findings have led them to warn fathers who smoke and drink to be aware they are potentially not just damaging themselves, but also their heirs.
The study by scientists from the University of Idaho in the U.S. suggests that a father's health plays a greater role in the health of future generations than has been thought.
The team led by Matthew Anway tested the effects of a hormone-disrupting fungicide chemical called vinclozolin on embryonic rats and found the chemical altered genes in the sperm, including some associated with human prostate cancer.
The rats exposed to the chemical showed signs of damage and overgrowth of the prostate, infertility and kidney problems and the defects were also present in animals four generations later.
The scientists admit that the rats were exposed to very high levels of vinclozolin but say their work shows that once toxins cause defects in sperm they can be passed down the generations.
Professor Cynthia Daniels, from Rutgers University in New Jersey, an expert on male and female reproduction, says it has been found that men who drank a lot of alcohol have increased rates of sperm defects and nicotine from tobacco also found its way into seminal fluid as well as blood.
Professor Daniels advises moderation for young couples and points out that substances which can have an impact on reproduction are often also carcinogenic.
Fertility experts say the DNA in sperm cells is more tightly packed than in other cells, and so, to some extent, is protected from damage, however, once sperm cell DNA is damaged, it has no mechanism by which to effect repairs.
They advise any man trying for a baby to lead as healthy a lifestyle as possible as heavy smoking and drinking undoubtedly results in sperm damage and possibly damage to the DNA of the sperm.
However the good news is that male sperm is produced continuously in a 74-day cycle, so the body does cleanse itself over time.
The study was presented to the American Association for the Advancement of Science (AAAS) in Boston USA.