Extensive scientific studies indicate that there are significant health and environmental effects associated with particulate matter (PM) and ground-level ozone. These pollutants are linked to serious health impacts including chronic bronchitis, asthma, and premature deaths. Other effects include reduced visibility in the case of PM, and crop damage and greater vulnerability to disease in some tree species in the case of ozone. In June 2000 the federal, provincial and territorial governments except Quebec signed the Canada-wide Standards for Particulate Matter (PM) and Ozone. These standards committed governments to significantly reduce PM and ground-level ozone by 2010. In 2012 ministers adopted the Air Quality Management System as a new comprehensive approach to managing air issues. Included in the system are Canadian Ambient Air Quality Standards for Fine Particulate Matter and Ozone, which replace these Canada-wide standards.