Almost 150 fines and 2800 formal warning letters were sent to people who threw cigarette butts from cars in the final three months of last year, including while bushfires were raging in the Blue Mountains.
The latest figures from the Environment Protection Authority reveal that between September 1 and December 31, EPA officers fined an average 50 people a month for throwing burning butts out car windows.
Another 2858 people were sent formal warning letters after other motorists reported them to the EPA.
Motorists can be fined $200 for littering from a car but throwing a burning cigarette during fire seasons is considered ''aggravated littering'' and the fine is increased to $375. Cigarette butts and other human activity, ranging from arson to fires accidentally lit by children, or falling power lines, are responsible for more than 90 per cent of bushfires in NSW.
The NSW Rural Fire Service's figures show there were 6381 bush, scrub and grass fires between July last year and January 21 this year, including 4756 which were the result of human activity.
Of those, 2804 were investigated and 209 were classed as arson. Lightning strikes caused 546 bushfires.
An analysis of Australian bushfires over the past decade found that natural events, most commonly started by lightning strikes, caused only 6 per cent of bushfires in NSW.
Prescribed burns account for more than 5 per cent of fires, 36 per cent of fires are started suspiciously and more than 13 per cent are the result of arson, according to the Australian Institute of Criminology.
The EPA's figures for cigarette butts coincide with one of the worst bushfire periods in NSW in decades.
October 17 was the most devastating day, when fire ravaged the Blue Mountains, destroying more than 200 homes.
Senior bushfire researcher at the University of Wollongong Trent Penman said contrary to popular belief natural causes were responsible for fewer bushfires than people and their activities were the overwhelming culprits. ''At times we are not only at risk but we create that risk,'' Dr Penman said.
Most human-related ignitions were within two kilometres of homes and 200 metres of roads, he said.
Geoff Cary, project leader at the Bushfire Co-operative Research Centre, said falling power lines played a significant role in the 1983 Ash Wednesday, 2009 Black Saturday and several bushfires this summer.
''A significant number of fatalities [in bushfires] can be attributed to power lines,'' Dr Cary said this week.
Dr Cary said burying power lines would reduce bushfires but it would come at a prohibitive cost.
A spokeswoman for the EPA said the public could report pollution from vehicles to the authority's environment hotline, online or using the EPA's mobile phone app.
''These avenues for reporting littering from motor vehicles are very important tools that the EPA uses to discourage littering and to act on incidents,'' she said.
''Reports from EPA staff and other trained officers about littering from motor vehicles result in penalty notices being issued to vehicle owners, while reports from members of the public result in the issuing of a formal warning.''
Into the Line of Fire Exhibition, featuring the work of Fairfax photographers, is on display at the State Library, Macquarie Street foyer until April 13.
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