Usually animals are used to test many poisonous substances. The lead toxicity has created public problem all around. Exposure to lead to a large extent may lead to nervous damage, less circulation. In children such exposure may cause decreased intelligence.

The macaques are very close to humans and share similarity. The Asian monkeys provide many early warnings to toxic exposure. Humans and macaques are similar anatomically, physiologically and behaviorally. Livings in the environment of human’s macaques have adjusted to the environment of polluted vehicles, disposed garbage, industrial waste.

The macaques are also exposed to toxic substances such as lead as humans. JONES ENGEL and her team made research by taking the samples of hair of macaques. Test showed that the macaques have similar responses when exposed to toxic substances.