I assume, k.forrest that you are hetrosexual? To talk about fellow human beings, who had had utterly no choice in their sexuality, as the "effect causing the population decline" is just little disrespectful. Also, all males have oestrogen in their blood stream throughout their lives, irrespective of their sexuality. The hormone oestrogen does not last very long, before it simply disintergrates. The only reason it remains is because the body keeps it topped up. Oestrogen would not survive water treatment facilities in the UK, and even if it did, it would have no affect on the sexuality of a developing baby. Sexuality, as far as we know, is decided at the point of contraception, giving the grown adult no choice. I understand you were not out to denounce homosexuality, but to pose the question is a little unfair. Homosexuality and hetrosexuality both exist, and therefor should be treated equally. just becase Hetrosexuality covers the majority of the population does not mean you can talk of other sexualities in such a way. But if i have failed to enlighten you, just stop drinking tap water, and let the 'population decline' continue in the knowlege you wont turn gay because your drinking Evian.