World environmental leaders gather in Kigali, Rwanda, October 10-14 in an effort to finalize an agreement on limiting hydrofluorocarbons (HFCs), gases used as refrigerants that also boost greenhouse warming.

"California will tighten rules on how much farmers can use a common pesticide listed by the nation's most productive agricultural state as a chemical known to cause cancer, regulators said Thursday."

"Polychlorinated biphenyls, or PCBs, are industrial chemicals so toxic that Congress banned them 40 years ago. Research has shown that they can cause a range of health concerns, including cancer and neurological problems such as decreased IQ. And yet, because they were commonly used in building materials for decades, they continue to contaminate classrooms in between 13,000 and 26,000 schools nationwide, according to Harvard researchers."

"For Nayesa Walker, the clock started ticking just over a month ago. On Sept. 1, she was given 60 days to find a new home after East Chicago Mayor Anthony Copeland abruptly announced that the public housing complex where she and her three children live would be demolished. The land is contaminated with lead and arsenic."

"A Canadian farming federation and an anti-GMO network are separately calling on the federal Competition Bureau to review the possible implications of Bayer's $66 billion US takeover of seed giant Monsanto."

"The Chemical Safety Board brought voted Wednesday evening to approve the final report and recommendations that were the result of a more than two and a half year investigation into a Charleston chemical leak."

"A loose coalition of more than 100 countries, including the US and European nations, is pushing for an early phase-out of hydrofluorocarbons (HFCs), a powerful greenhouse gas that if left unchecked is set to add a potentially disastrous 0.5C to global temperatures by the end of the century."

"Environmentalists are warning the Environmental Protection Agency (EPA) that its draft plan to continue allowing oil and gas companies to dump unlimited amounts of fracking chemicals and wastewater directly into the Gulf of Mexico is in violation of federal law."

"Bayer and Syngenta criticised for secrecy after unpublished research obtained under freedom of information law linked high doses of their products to damage to the health of bee colonies".

"The Food and Drug Administration, under public pressure to start testing samples of U.S. food for the presence of a pesticide that has been linked to cancer, has some early findings that are not so sweet."