* Industrial product prices fall 0.3 pct on metals, gasoline
* Raw materials prices down 1.5 percent
OTTAWA, Oct 29 (Reuters) - Lower prices for primary metal products and gasoline triggered a 0.3 percent decline in Canada's industrial producer prices in September from August, following three straight months of advances, Statistics Canada said on Tuesday.
Raw materials prices also fell in the month for the first time since April, down 1.5 percent on lower crude oil prices.
Analysts surveyed by Reuters had forecast, on average, a 0.2 percent drop in the industrial product price index and a 0.7 percent slide in the raw materials price index.
Year on year, industrial prices were up 1 percent and raw materials gained 2.1 percent.
Statscan said primary metals were the largest contributor to the decline in producer prices, particularly aluminum, copper and copper alloy products.
Petroleum and coal products fell 0.4 percent, dragged down by a 1.9 percent drop in gasoline.
The appreciation of the Canadian dollar against the U.S. dollar in September likely dampened prices for Canadian exporters who report in US dollars. Without the exchange rate effect, producer prices would have fallen just 0.1 percent, the agency estimated.