BERLIN (AP) — Germany's environment minister is rejecting calls for a halt to roadside emissions testing, after some 100 doctors suggested existing limits on pollutants from cars were unfounded.

Svenja Schulze said Monday the thresholds are backed by scientific research into the harmful effects of fine particle pollution and nitrogen dioxide.

Schulze told reporters in Berlin that "at the moment there is no reason to demand additional reviews or moratoriums" on emissions tests, which have prompted some cities to consider bans on diesel cars.

A letter signed by 107 experts, most of them doctors, sparked a debate last week Germany about the basis for pollution prevention measures.

The Forum of International Respiratory Societies, a global body with over 70,000 members, says fine particle pollution can lead to both acute and chronic medical conditions.