Carbon Monoxide is not a poison in the classical sense as say Strychnine, Arsenic, or Cyanide. Carbon Monoxide is toxic because it displaces oxygen and causes asphyxiation while leaving zero toxic residue behind. Carbon Dioxide and Nitrogen, the two most prevalent compounds found in engine exhaust, are also toxic in this same manner.
Carbon Monoxide in particular combines with hemoglobin to produce carboxyhemoglobin. This conversion from hemoglobin to carboxyhemoglobin makes the hemoglobin molecule incapable of delivering oxygen to the organism and results in asphyxiation. Because CO is highly unstable, any CO (Carbon Monoxide) that is not converted to carboxyhemoglobin rapidly oxidizes to Carbon Dioxide. Residual CO is not left behind in the organism because upon the creation of a high enough concentration of carboxyhemoglobin to become toxic, breathing (and therefore CO intake) stops. This all happens quickly, silently, and often without notice by the effected organism which is why CO is considered to be dangerous and also why many municipalities are requiring CO detectors to be installed in homes today.
The Crittergetter & Engine Exhaust:
Common Fertilizers, Pesticides, and Pest Control Products:
Of 30 commonly used lawn pesticides, 19 are linked with cancer or carcinogenicity, 13 are linked with birth defects, 21 with reproductive effects, 26 with liver or kidney damage, 15 with neurotoxicity, and 11 with disruption of the endocrine (hormonal) system. Of those same pesticides, 17 are detected in groundwater, 23 have the ability to leach into drinking water sources, 24 are toxic to fish and other aquatic organisms vital to our ecosystem, 11 are toxic to bees, and 16 are toxic to birds. And this is just the "short list". Take a look at Pesticide Hazards and Safe Pest Management for even more good news, or see Beyond Pesticides searchable database for an analysis of just about everything under the sun. Please take note; It is very common that the "inert ingredients" found in many of these items are more toxic than what is listed as the "active ingredient". Please print either of the linked PDF´s and take them to the shed.