Residue tolerances for pesticides are established at how many times lower than the concentration tolerated by test animals?

The correct answer reflects the regulatory framework in place for establishing residue tolerances for pesticides, which are set significantly lower than the concentrations tolerated by test animals to ensure safety for human consumption and environmental health. This factor of 100 to 1000 times is a critical aspect of risk assessment.

Establishing residue tolerances at this level provides a safety margin that accounts for potential variances in individual sensitivities as well as the cumulative effects of exposure to multiple pesticides. This precautionary principle helps safeguard human health and the environment by ensuring that even in exceptional cases where exposure could occur, the levels will be within safe limits.

The other options indicate broader ranges, but the 100 to 1000 times lower threshold strikes an appropriate balance between safety and practical considerations for pesticide use and consumer protection.