Occupational and Environmental Exposure of Automobile Mechanics and Nonautomotive Workers to Airborne Manganese Arising from the Combustion of Methylcyclopentadienyl Manganese Tricarbonyl (MMT)

Sierra, Patricia; Loranger, Sylvain; Kennedy, G.; Zayed, Joseph

doi:10.1202/0002-8894(1995)056<0713:oaeeoa>2.0.co;2

Cited by 9 publications

(14 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, recent work on Mn has suggested that chronic long-term exposures potentially may be linked to the emergence of idiopathic Parkinson disease in susceptible populations (1)(2)(3) and future ambient Mn levels may increase due to the use of gasoline additive methyl-cyclopentadienyl manganese tricarbonyl (4)(5). Interest in ambient exposures to transition metals, with iron being the most prevalent species, is related to initial data suggesting that they might be linked to cardiovascular outcomes of particulate matter exposures (6)(7).…”

Section: Introductionmentioning

confidence: 99%

Elevated Airborne Exposures of Teenagers to Manganese, Chromium, and Iron from Steel Dust and New York City's Subway System

Chillrud

Epstein

Ross

et al. 2003

Environ. Sci. Technol.

206

131

View full text Add to dashboard Cite

There is increasing interest in potential health effects of airborne exposures to hazardous air pollutants at relatively low levels. This study focuses on sources, levels, and exposure pathways of manganese, chromium, and iron among inner-city high school students in New York City (NYC) and the contribution of subways. Samples of fine particulate matter (PM2.5) were collected during winter and summer over 48 h periods in a variety of settings including inside homes, outdoors, and personal samples (i.e., sampling packs carried by subjects). PM2.5 samples were also collected in the NYC subway system. For NYC, personal samples had significantly higher concentrations of iron, manganese, and chromium than did home indoor and ambient samples. The ratios and strong correlations between pairs of elements suggested steel dust as the source of these metals for a large subset of the personal samples. Time-activity data suggested NYC subways as a likely source of these elevated personal metals. In duplicate PM2.5 samples that integrated 8 h of underground subway exposure, iron, manganese, and chromium levels (>2 orders of magnitude above ambient levels) and their ratios were consistent with the elevated personal exposures. Steel dust in the NYC subway system was the dominant source of airborne exposures to iron, manganese, and chromium for many young people enrolled in this study, with the same results expected for other NYC subway riders who do not have occupational exposures to these metals. However, there are currently no known health effects at the exposure levels observed in this study.

show abstract

Section: Introductionmentioning

confidence: 99%

Elevated Airborne Exposures of Teenagers to Manganese, Chromium, and Iron from Steel Dust and New York City's Subway System

Chillrud

Epstein

Ross

et al. 2003

Environ. Sci. Technol.

206

131

View full text Add to dashboard Cite

show abstract

“…Mining, steel manufacturing and welding represent occupational exposures that are associated with Mn exposures to high Mn levels (Tanaka and Lieben, 1969; Cook et al, 1974; Myers et al, 2003). An organic Mn compound, methylcyclopentadienyl manganese tricarbonyl (MMT), used as an octane booster or anti-knock agent in gasoline, has also been shown to cause adverse health effects in humans in Canada and elsewhere (Abbott et al, 1987; Sierra et al, 1995; Dobson et al, 2004). …”

Section: - Introductionmentioning

confidence: 99%

Rat brain endothelial cells are a target of manganese toxicity

Santos

Milatović

et al. 2010

Brain Research

View full text Add to dashboard Cite

Manganese (Mn) is an essential trace metal, however exposure to high Mn levels can result in neurodegenerative changes resembling Parkinson´s disease (PD). Information on Mn´s effects on endothelial cells of the blood-brain barrier (BBB) is lacking. Accordingly, we tested the hypothesis that BBB endothelial cells are a primary target for Mn-induced neurotoxicity. The studies were conducted in an in vitro BBB model of immortalized rat brain endothelial (RBE4) cells. ROS production was determined by F2-Isoprostane (F2-IsoPs) measurement. The relationship between Mn toxicity and redox status was investigated upon intracellular glutathione (GSH) depletion with diethylmaleate (DEM) or L-buthionine sulfoximine (BSO). Mn exposure (200 or 800 µM MnCl2 or MnSO4) for 4 or 24h led to significant decrease in cell viability vs. controls. DEM or BSO pre-treatment led to further enhancement in cytotoxicity vs. exposure to Mn alone, with more pronounced cell death after 24h DEM pre-treatment. F2-IsoPs levels in cells exposed to MnCl2 (200 or 800 µM), were significantly increased after 4h and remained elevated 24h after exposure compared with controls. Consistent with the effects on cell viability and F2-IsoPs, treatment with MnCl2 (200 or 800 µM) was also associated with a significant decrease in membrane potential. This effect was more pronounced in cells exposed to DEM plus MnCl2 vs. cells exposed to Mn alone. We conclude that Mn induces direct injury to mitochondria in RBE4 cells. The ensuing impairment in energy metabolism and redox status may modify the restrictive properties of the BBB compromising its function.

show abstract

“…Determination of Mn T and Mn R All the filters were analyzed by INAA (Kennedy, 1990). The detailed methodology related to the chemical analysis of Mn has been described in two previous papers Sierra et al, 1995). A number of randomly selected blank filters with the same size were analyzed.…”

Section: Sampling Of Atmospheric Mnmentioning

confidence: 99%

“…Brault et al, 1994;Loranger et al, 1994Loranger et al, , 1996. Exposure of the general population to Mn emanating from MMT seems to be low compared to the contribution of Mn from other industrial and natural sources , 1997aSierra et al, 1995;Zayed et al, 1994). Nevertheless, it was observed in a recent study that some atmospheric concentrations in specific areas near considerable traffic density were higher than the U.S. Environmental Protection Agency (EPA) reference concentration (RfC) of 50 ng/m 3 for respirable Mn (Zayed et al, 1999a).…”

mentioning

confidence: 91%

“…Many studies have been conducted in the Montreal area (Canada) in order to evaluate environmental contamination and human exposure to Mn from the combustion of MMT , 1997a, 1997bSierra et al, 1995;Zayed et al, 1994Zayed et al, , 1996. Results show that road-side air, soil, plant, and animal tissues were elevated in Mn concentrations, probably related to high traffic density 504 C. THIBAULT ET AL.…”

mentioning

confidence: 93%

See 1 more Smart Citation

Preliminary Assessment of Atmospheric Methylcyclopentadienyl Manganese Tricarbonyl and Particulate Manganese in Selected Urban Sites

Thibault

Kennedy

Gareau

et al. 2002

Journal of Toxicology and Environmental Health, Part A

Self Cite

View full text Add to dashboard Cite

Methylcyclopentadienyl manganese tricarbonyl (MMT: C9H7MnO3) is an organometallic additive that has been used since 1976 as an octane enhancer in Canadian unleaded gasoline. Very few studies have determined its atmospheric concentrations and only one study offers recent data on its ambient level. This preliminary study aims to assess atmospheric concentrations of MMT and respirable and total Mn (Mn(R) and Mn(T) in selected sites, at two underground car parks and one gasoline station, related to high levels of automobile traffic. It is also an investigation of the applicability of the current analytical method. In total, 34 air samples were collected using a Gil-Air portable pump during 4 consecutive days and then were analyzed by neutron activation analysis. The concentrations vary between 40 and 104 ng/m3 for Mn(R), 146 and 204 ng/m3 for Mn(T) and 6 and 128 ng/m3 for MMT (including ultrafine particulates, Mn(UF). Of the 12 Mn(R) results, 7 showed concentrations greater than the U.S. EPA reference concentration (RfC = 50 ng/m3). The ratios of Mn(R) to Mn(T) varied from 0.20 to 0.65 with a mean of 0.38. The results for MMT and Mn(UF) raise serious doubts about the specificity of the sampling and chemical analysis methodology proposed by the Occupational Safety and Health Administration (OSHA) for MMT in air.

show abstract

Occupational and Environmental Exposure of Automobile Mechanics and Nonautomotive Workers to Airborne Manganese Arising from the Combustion of Methylcyclopentadienyl Manganese Tricarbonyl (MMT)

Cited by 9 publications

References 0 publications

Elevated Airborne Exposures of Teenagers to Manganese, Chromium, and Iron from Steel Dust and New York City's Subway System

Elevated Airborne Exposures of Teenagers to Manganese, Chromium, and Iron from Steel Dust and New York City's Subway System

Rat brain endothelial cells are a target of manganese toxicity

Preliminary Assessment of Atmospheric Methylcyclopentadienyl Manganese Tricarbonyl and Particulate Manganese in Selected Urban Sites

Contact Info

Product

Resources

About