The incidence of hypospadias - a birth defect of the male urethra in which the opening forms abnormally somewhere along the shaft of the penis instead of at the tip - has increased in Israel by 30 percent in recent years due to exposure to pesticides in food and chemicals in the home environment, according to Prof. Yona Amitai, a veteran toxicologist and pediatrician and former head of the Health Ministry's Mother, Child and Adolescent Health Department. Speaking in Herzliya Monday at the first conference of the Environmental and Health Fund, Amitai said that 309 baby boys were born in Israel with this defect in 2001 and that the figure rose to 434 in 2005. Based on similar experience in other developed countries, it is believed that the increase is due to the mother's exposure to chemicals and toxins during pregnancy that disrupt normal hormonal activity. Another consequence of such exposure, he said, is cryptorchism or an undescended testis, in which they remain inside the body. Hypospadias is among the most common birth defects of the male genitalia, with cryptorchidism second. Reported incidences range from one in 4,000 to one in 125 male births. Most defects are not inherited and do not run in the family. Chemicals that disrupt the endocrine system and interact with steroid receptors are believed to be responsible for most cases. Among the disruptors are DDT, phthalates and polychlorinated biphenyls (PCBs), common components of most baby bottles. Some research suggests that women who follow a vegetarian diet and eat a lot of food with high levels of phytoestrogens, such as soy, have a higher risk of hypospadias in their sons. Several teratogenic chemicals and various drugs have been shown to cause hypospadias in animals by interfering with androgen action in the embryo. Some experts believe endocrine disruptors may be interfering with human hormones as well. Hypospadias usually causes no functional urination problem except that the urine streams to the side rather than straight. The main complaint is esthetic, but it may also interfere with ejaculation and cause fertility problems. Most cases of hypospadias can be corrected in an operation during the first year of life. The newly formed Environment and Health Foundation will spend about $2 million a year in the next few years on research into the environmental influences on health in Israel. Amitai said that environmental factors can also be blamed for reducing the amount of sperm in semen and for causing girls to enter adolescence prematurely.