Chronic solvent-induced encephalopathy
Chronic solvent-induced
Symptoms and signs
Two characteristic symptoms of CSE are deterioration of memory (particularly short-term memory), and attention impairments. There are, however, numerous other symptoms that accompany to varying degrees. Variability in the research methods studying CSE makes characterizing these symptoms difficult, and some may be questionable regarding whether they are actual symptoms of solvent-induced syndromes, simply because of how infrequently they appear.[7] Characterizing of CSE symptoms is more difficult because CSE is currently poorly defined, and the mechanism behind it is not understood yet.[citation needed]
Neurological
Reported neurological symptoms include
Sensory alterations
A 1988 study indicated that some solvent-exposed workers developed
Psychological
Psychological symptoms of CSE that have been reported include
Causes
Organic solvents that cause CSE are characterized as
Exposure to solvents can occur by inhalation, ingestion, or direct absorption through the skin. Of the three, inhalation is the most common form of exposure, with the solvent able to rapidly pass through lung membranes and then into fatty tissue or cell membranes. Once in the bloodstream, organic solvents easily cross the blood–brain barrier, due to their lipophilic properties.[4] However, the sequence of effects that these solvents have on the brain is not yet fully understood.[5]
Diagnosis
Due to its non-specific nature, diagnosing CSE requires a multidisciplinary "Solvent Team" typically consisting of a
Furthermore, CSE must be diagnosed "by exclusion". This means that all other possible causes of the patient's symptoms must first be ruled out beforehand. Because screening and assessing for CSE is a complex and time-consuming procedure requiring several specialists of multiple fields, few cases of CSE are formally diagnosed in the medical field. This may, in part, be a reason for the syndrome's lack of widespread recognition. The solvents responsible for neurological effects dissipate quickly after an exposure, leaving only indirect evidence of their presence, in the form of temporary or permanent impairments.[citation needed]
Brain imaging techniques which have been explored in research have shown little promise as alternative methods to diagnose CSE.
Classification
Introduced by a working group from the
Treatment
Like diagnosis, treating CSE is difficult because it is vaguely defined and data on the mechanism of CSE effects on neural tissue are lacking. There is no existing treatment that is effective at completely recovering any neurological or physical function lost due to CSE. This is believed to be because of the limited regeneration capabilities in the central nervous system. Furthermore, existing symptoms of CSE can potentially worsen with age. Some symptoms of CSE, such as depression and sleep issues, can be treated separately, and therapy is available to help patients adjust to any untreatable disabilities. Current treatment for CSE involves treating accompanying psychopathology, symptoms, and preventing further deterioration.[3][5]
History
Cases of CSE have been studied predominantly in northern Europe, though documented cases have been found in other countries such as the United States, France, and China. The first documented evidence for CSE was in the early 1960s from a paper published by Helena Hanninen, a Finnish neuropsychologist. Her paper described a case of workers who developed carbon disulfide intoxication at a rubber manufacturing company and coined the term "psycho-organic syndrome".[citation needed] Studies of solvent effects on intellectual functioning, memory, and concentration were carried out in the Nordic countries, with Denmark spearheading the research. Growing awareness of the syndrome in the Nordic countries occurred in the 1970s.[citation needed]
To reduce cases of CSE in the workforce, a diagnostic criterion for CSE appeared on information notices in occupational disease records in the European Commission. Following, from 1998 to 2004, was a health surveillance program for CSE cases among construction painters in the Netherlands. By 2000, a ban was put into action against using solvent-based paints indoors, which resulted in a considerable reduction of solvent exposure to painters. As a result, the number of CSE cases dropped substantially after 2002. In 2005–2007, no new CSE cases were diagnosed among construction painters in the Netherlands, and no occupational CSE has been encountered in workers under thirty years of age in Finland since 1995.[1][11]
Though movements to reduce CSE have been successful, CSE still poses an issue to many workers that are at occupational risk. Statistics published in 2012 by Nicole Cherry et al. claim that at least 20% of employees in Finland still encounter organic solvents at the workplace, and 10% of them experience some form of disadvantage from the exposure. In Norway, 11% of the male population of workers and 7% of female workers are still exposed to solvents daily and as of 2006, the country has the highest rate of diagnosed CSE in Europe.[2][11] Furthermore, due to the complexity of screening for CSE, there is still a high likelihood of a population of undiagnosed cases.[1]
Occupations that have been found to have higher risk of causing CSE are painter, printer, industrial cleaner, and paint or glue manufacturer.