The works required the removal of tons of soil poisoned with lindane residues. The number of insects resistant to cyclodienes and lindane approached 300 by 1989. Whether lindane is an endocrine disruptor is unclear. In areas where DDT resistance is encountered, malathion, propoxur or lindane is used. The common poison used in Lindane and it most commonly used in Cameroon. Other treatments include lindane, benzyl benzoate, crotamiton, malathion, and sulfur preparations. By comparison, the state of California imposes a lower MCL for lindane of 19 ppt. Lindane is a second line treatment due to concerns of toxicity. The EPA and WHO both classify lindane as "moderately" acutely toxic. Of the pharmaceutical components found in drinking water, the EPA only regulates lindane.