41.   Certain genes and environmental factors, like exposure to a pesticide called rotenone, ultimately increase the misfolding process.

42.   Claudio said that much more study is needed to establish a definite causal link between asthma and many environmental factors.

43.   Common environmental factors might also play a role.

44.   Despite the concerns of some residents, in most cases researchers have yet to show any definitive link between cancer clusters and environmental factors.

45.   Environmental factors have a lot to do with the feel.

46.   Environmental factors seemed to creep up everywhere.

47.   Environmental factors such as diet and lifestyle play important roles.

48.   Environmental factors, like staff shortages and subspecialization, are less easily remedied.

49.   Environmental factors come into play.

50.   Experts have differences in opinion about whether the deaths are the result of a single pathogen or oaks weakened by drought or other environmental factors.