Product quality and safety tester Intertek said the rate of organic revenue growth is slowing, as expected, in the second half of the year.Total year on year revenue growth for the January to October (inclusive) period was 28%, or 8% using constant exchange rates (CER). Organic revenue growth at CER was 4%.The company said the slowdown in organic revenue growth was largely due to a temporary upsurge in the testing of children’s products a year ago as manufacturers responded to new US toys legislation.Reduced demand for volume related inspection services continued in the Oil, Chemical & Agri division and there was sustained lower demand in the Minerals market, the group said.Margins in all six divisions of the group remained at much the same levels as seen at the half year stage.‘We continue to demonstrate our resilience in the face of challenging markets by growing organic revenue and operating profit year to date. This is despite the high comparables due to one-off testing in the Consumer Goods division and no improvement so far in the volume related business, which accounts for approximately 30% of the group's revenue,’ said Wolfhart Hauser, chief executive officer of Intertek.