61.   In fact, he said, if harmful chemicals are the issue, there are plenty already inside the house.

62.   In general, the chemicals are present in the environment in minuscule quantities whereas the known effects occurred at high concentrations.

63.   In this exercise, civilian casualties had been evacuated before the team arrived, and local hospitals needed to know what chemicals had been dispersed that made them sick.

64.   In sufficient concentrations, the chemical can be a major health hazard.

65.   It is unclear, he conceded, whether these chemicals are a cause or effect of HIV resistance.

66.   It is treated with chemicals to make it fire resistant, but no one has proved to me how long those chemicals are effective.

67.   It could also help show if the chemicals are dangerous to bees and earthworms, and how effective they are against pests.

68.   It says the chemical should not be included on a list of approved substances pending more study.

69.   J.R. Khalfan, one of two brothers who own Kaltech and is a company director, said he did not believe the chemicals were a cause of the explosion.

70.   Keeping your yard mowed and trimmed will help greatly to reduce flea and tick and mosquito problems, and several new chemicals are highly effective for treating the yard.