low temperatures. Unremovable textiles such as mattresses can be steamed to at least and this method can penetrate deep into the textile to effectively kill bed bugs in, potentially, under one minute. Heating tents or chambers can be used for infested materials or entire rooms can be heated to at least to effectively eradicate infestation. There is no evidence to indicate that a combination of non-chemical methods plus insecticides is more effective than non-chemical methods alone with regards to eradication of bed bug infestations. Insecticides are mostly ineffective for the eradication of bedbug infestations as most bedbugs are resistant to insecticides, including pyrethroids which are found in approximately 90% of commercial grade insecticides. Furthermore, insect foggers (known as "bug bombs") are ineffective in the eradication of bed bug infestation as they are unable to penetrate bed bug harborages. Resistance to pesticides has increased significantly over time, and there are concerns about harm to health from their use. Once established, bed bugs are extremely difficult to get rid of. Bed bugs are particularly difficult to eradicate in apartment complexes as harbors can exist in other areas of the building when single units are treated. Mechanical approaches, such as vacuuming up the insects and heat-treating or wrapping mattresses, are effective. An hour at a temperature of or over, or two hours at less than kills them. This may include a domestic clothes drier for fabric or a commercial steamer. Bed bugs and their eggs will die on contact when exposed to surface temperatures above and a steamer can reach well above . A study found 100% mortality rates for bed bugs exposed to temperatures greater than for more than 2 minutes. The study recommended maintaining temperatures of above for more than 20 min to effectively kill all life stages of bed bugs, and because in practice treatment times of 6 to 8 hours are used to account for cracks and indoor clutter. This method is expensive and has caused fires. Starving bedbugs is not effective, as they can survive without eating for 100 to 300 days, depending on temperature. that no truly effective insecticides were available. Insecticides that have historically been found effective include pyrethroids, dichlorvos, and malathion. Resistance to pesticides has increased significantly in recent decades. The carbamate insecticide propoxur is highly toxic to bed bugs, but it has potential toxicity to children exposed to it, and the US Environmental Protection