Over the past 5 years, the use of phenyl-2-propanone as the primary precursor for methamphetamine has increasingly been replaced by the ephedrine reduction method. Recognizing the simplicity of the ephedrine process, the ease of obtaining precursor chemicals, and flexibility in laboratory sites, Mexican drug organizations have extended their influence in the stimulant market for profit. Using previously established networks, these organizations are producing and distributing d-methamphetamine, a drug twice as potent as its predecessor (dl-methamphetamine) and with a longer-lasting high than cocaine. The manufacture of d- methamphetamine, however, poses environmental hazards, and the most dangerous chemicals typically include hydriodic acid and red phosphorus. These substances may emanate toxic gases, hydriodic acid vapors, and phosphine gas. Although both can be easily detected, exposure to or inhalation of either chemical can cause respiratory damage, chemical burns, or even death. Red phosphorus, in both gaseous and solid forms, presents additional problems because it is unstable and flammable, and exposure to spark or flame can result in chemical fires and multiple explosions. In addition, traces of red phosphorus will likely remain on discarded materials and equipment, presenting a flammable hazard for 3 to 4 decades. The high costs of removing containers used in drug production, contaminated equipment, and obvious waste fall on law enforcement, property owners, environmental agencies, health departments, and taxpayers in general. As Mexican drug trafficking organizations demonstrate their ability to sustain large-scale clandestine laboratory operations inside U.S. borders, the amount of hazardous waste generated will continue to cause serious environmental damage and pose immediate and long-term health risks to individuals. 2 tables and 5 figures