• Ionizing radiation: *atomic weapons, radioiodine, radiation therapy
• Infections
• Metabolic imbalance: alcoholism, diabetes, and congenital heart block
• Drugs and environmental chemicals : **13-cis-retinoic acid

The status of some of the above substances (e.g. diphenylhydantoin) is subject to debate, and many other compounds are under varying degrees of suspicion. These include Agent Orange, nicotine, aspirinand other drugs.

Other compounds are known as severe teratogens based on veterinary work and animal studies, but aren't listed above because they have not been studied in humans, e.g. cyclosporine. Teratogenic effects also help to determine the pregnancy category assigned by regulatory authorities; in the United States, a pregnancy category of X, D, or C may be assigned if teratogenic effects (or other risks in pregnancy) are documented or cannot be excluded.

**Isotretinoin (13-cis-retinoic-acid; brand name Accutane), which is often used to treat severe acne, is such a strong teratogen that just a single dose taken by a pregnant woman may result in serious birth defects. Because of this effect, most countries have systems in place to ensure that it is not given to pregnant women, and that the patient is aware of how important it is to prevent pregnancy during and at least one month after treatment. Medical guidelines also suggest that pregnant women should limit vitamin A intake to about 700 μg/day, as it has teratogenic potential when consumed in excess.

Sherlin's writing starts here .

*Atomic weapons . Still remember my last post said about ''there is a part of japan ( don't know which area ) all the people there have this tetraogens thingy because last time this area / country bombed America and then the America bombed back and caused them the people there to have this sickness. ''

Yeah, thats what it is trying to say here. The American bombed the area with atomic bombs . Not only the environment can do harm to us but other things that we do in our daily lives . There are example above . Even though it says that it is potentially preventable but we still have to be cautions about it .

There is never 100% assure that our future people will not get it . What we have to do now it prevent it . The first thing we have to do it control pollution .

To read more about it please go to wikipedia :))

p.s About the occupational exposures , it means that ( thats what i know from my teachers ) we the people who work in the chemical industry are the people who most likely to get these diseases . Because all the things that we did over at the chemical plant are mostly harmful and toxic . We found ways to prevent it but it can never be done . Even though our pay is high but it is not a very glory industry as alot of people died and got accident and stuff .

But never let this kind of thing makes you not do the things you want in life la . I'm still going to petrolchemical . I don't care if this kind of thing is going to make my self esteem down or what . As long as i am happy with my work and become successful . Not many people like the job i am doing because we have to do night shift and stuff and we don't have alot of time with our family .