These noxious fumes include dioxins and furans. A local doctor said the noxious fumes were unhealthful. These pollutants contribute to global warming, acid rain, and noxious smells if released. If released, these pollutants contribute to global warming, acid rain, radiation, and noxious smells. Many "Hypericum" species are regarded as invasive species and noxious weeds. Some Tenebrionidae use their posture for releasing noxious chemicals to warn off predators. These contaminants contribute to the formation of noxious sea foam through adsorption onto bubbles. These agents increase the sensitivity of nociceptors to noxious stimuli. Crayfish have peripheral nerve fibres which are responsive to noxious stimuli. It is now regarded as a noxious, invasive weed. VR1 is essential for the inflammatory sensitization to noxious thermal stimuli. The effect is to make people less aware and less reactive to noxious stimuli. Catalytic converters have proven to be reliable and effective in reducing noxious tailpipe emissions. Some prey animals are able to eject noxious materials to deter predators actively. The role of NMDA receptors in non-inflammatory noxious stimuli was examined.