Deleterious (adjective)

1. Harmful or dangerous to health; causing injury or damage.
2. Having a harmful effect on something; damaging or detrimental.

Origin:

Late 16th century; earliest use found in robert burton. from latin deleterius, from deleter (stem deleteri-) harmful, detrimental, from delere to destroy.

Examples:

1. The chemical is known to have deleterious effects on the liver.
2. Smoking is a deleterious habit that can cause lung cancer.
3. The company's policies had a deleterious effect on employee morale.
4. His unhealthy diet had a deleterious effect on his health.
5. The long-term effects of exposure to the chemicals were found to be deleterious.