Neurological and Cognitive Recovery Following Abstinence from Petrol Sniffing

Abstract

Anecdotal observations suggest that neurological impairments associated with petrol (gasoline) sniffing resolve with abstinence, although these effects have not been proven empirically. Severe exposure to leaded petrol may induce a lead encephalopathy that extends beyond any acute intoxication and requires emergency hospital treatment. Previously, in chronic petrol sniffers, we showed neurological, saccadic, and cognitive abnormalities that were more severe in petrol sniffers with a history of hospitalization for lead encephalopathy, and that correlated with blood lead levels and the length of time of sniffing petrol. Ex-petrol sniffers showed a qualitatively similar but quantitatively less severe pattern of impairment. Petrol sniffing was stopped completely in one of the study communities by modifying social, occupational, and recreational opportunities. After 2 years, we obtained biochemical and neurobehavioral (neurological, saccade, and cognitive) data from all available participants of the earlier study including 10 nonsniffers and 29 chronic petrol sniffers, with six of these individuals previously receiving hospital treatment for lead encephalopathy. Here, we report that blood lead was reduced and that neurobehavioral impairments improved, and in many cases normalized completely. The most severe petrol-related neurobehavioral impairment was observed among individuals who had longer histories of abuse and higher blood lead levels, and among petrol sniffers with a history of lead encephalopathy. Those with the greatest extent of neurobehavioral impairment showed the greatest degree of improvement with abstinence, but were less likely to recover completely. This is the first direct evidence that neurological and cognitive impairment from chronic petrol sniffing ameliorates with abstinence and may recover completely.

Increased Anti-saccade Latency Is an Isolated Lingering Abnormality in Sydenham Chorea

“…The ocular motor and neuropsychologic tests used here are identical to those used in our previous studies based on Aboriginal Australians living in remote communities and have been described in detail in earlier publications (5,6). Ocular motor recordings were performed in a darkened room with the head stabilized, using a high-resolution infrared scleral reflectance technique (IRIS, Skalar; bandwidth DC to 100 Hz [23 dB]).…”

“…All subjects had been enrolled in a large study of substance abuse in remote Aboriginal communities in northern Australia (5,6), but neither the SC subjects nor the members of the healthy control group had histories of substance abuse or psychiatric illness. The study was approved by the relevant institutional ethics committees with input from an Aboriginal subcommittee.…”

Will modifying inhalants reduce volatile substance misuse? A review

“…Following representations from other remote Aboriginal communities in Queensland, the Northern Territory and Western Australia, the Commonwealth has also agreed to extend the new scheme beyond the boundaries of the original Comgas scheme. The first phase of the Opal scheme will be evaluated in 2005-2006. Leaded petrol is particularly neurotoxic and causes more severe and irreversible damage to users' brains than unleaded petrol (Cairney et al, 2005). Replacement of leaded with unleaded petrol for motor vehicles (now mandatory for environmental reasons) has resulted in decreases in petrolsniffing morbidity and mortality (Burns, Currie, & Powers, 1995).…”

“…Fuel gas misuse is implicated in a greater proportion of fatalities than any other inhalant (Field-Smith, Butland, Ramsey, & Anderson, 2005). Second, longterm inhalation of substances (in particular those containing toluene) is associated with cognitive dysfunction, dementia and wide-spread cerebellar damage (Kurtzman et al, 2001) with some potential for recovery on VSM abstinence (Cairney, Maruff, Burns, Currie, & Currie, 2005;Rosenberg, 1997). Other harms related to VSM include damage to the heart, liver and other organs, consequences of crimes committed while intoxicated, vulnerability to sexual and physical assault and intensification of marginalization as a result of associated stigma (Fairbairn & Murray, 2004;MacLean, 2005;Rosenberg, 1997).…”

Metabolic correlates of toluene abuse: decline and recovery of function in adolescent animals

“…Based on recent clinical data demonstrating a reversible cognitive impairment in adult petrol sniffers (Cairney et al 2005), we also hypothesized that toluene-induced changes in brain metabolic function would recover upon cessation from exposure. Previous efforts in our laboratory have been directed toward the development of an inhalation chamber that can indirectly assess the positive or negative reinforcing effects of inhaled solvents (Gerasimov et al 2003;Lee et al 2004).…”