Bhuie A K, Roy D N
Faculty of Forestry, University of Toronto, Ontario, Canada.
J Air Waste Manag Assoc. 2001 Sep;51(9):1288-301. doi: 10.1080/10473289.2001.10464350.
Methylcyclopentadienyl manganese tricarbonyl (MMT) has been used in Canada since 1976 as an antiknock agent in gasoline, completely replacing Pb in 1990. An early study of much higher Mn concentrations in gasoline showed that the combustion of MMT leads to the formation of inorganic manganese oxides, especially Mn3O4. Recent emission testing by Lawrence Livermore National Laboratory for Ethyl Corp. has shown that Mn is primarily emitted as a phosphate or sulfate along with minor amounts of oxides. The main objective of this research was to analyze the deposition of Mn from MMT to the terrestrial environment beside the major highways in the greater Toronto area (GTA), Canada. The results were compared with Pb and other trace elements such as Al, Ca, Fe, Mg, Cu, Zn, Na, and the Cl ion (water extractable) to study the behavior of Mn in soil. The study area was located near major Toronto highways 401 (urban) and 400 (rural), at 43 degrees 67' N and 79 degrees 37' W (latitude and longitude) (278,560 and 47,835 cars/day), respectively. Surface soil samples (0-5 cm depth) were collected at distances up to 40 m from the roadside. Parameters evaluated included total and available Mn and other trace elements, particle size, pH, organic content, and cation exchange capacity. Based on high traffic density along 401, higher Mn deposition was expected. No significant differences were found between the 401 and 400 Barrie (E(+1)) sites, attributable to the natural background levels of Mn or its contribution by other sources such as Mn-enriched road dust or naturally occurring crustal Mn. However, the 400 King City (E(+2)) site had significantly lower Mn levels than did the other three sites, 401 and 400 Barrie. This may be explained by the types of soil along the 401 and 400 sites. The King City site along 400 was found to be higher in sand content than were the 401 sites. A higher sand content could result in higher leaching of Mn to the bottom layer of the soil. Although MMT has been used continuously for approximately 25 years in Canada, its contribution to the terrestrial environment has been very low and has not significantly increased Mn levels along the highways, as demonstrated by this study.
自1976年以来，甲基环戊二烯三羰基锰（MMT）在加拿大被用作汽油中的抗爆剂，并于1990年完全取代了铅。一项早期对汽油中锰浓度高得多的研究表明，MMT的燃烧会导致无机锰氧化物的形成，尤其是Mn3O4。劳伦斯利弗莫尔国家实验室近期为乙基公司进行的排放测试表明，锰主要以磷酸盐或硫酸盐的形式排放，同时伴有少量氧化物。本研究的主要目的是分析加拿大大多伦多地区（GTA）主要高速公路旁MMT中的锰向陆地环境的沉积情况。将结果与铅以及其他微量元素（如铝、钙、铁、镁、铜、锌、钠）和氯离子（水溶态）进行比较，以研究锰在土壤中的行为。研究区域位于多伦多主要高速公路401（城市）和400（农村）附近，分别位于北纬43度67分、西经79度37分（纬度和经度）（每日车流量分别为278,560辆和47,835辆）。在距离路边最远40米处采集表层土壤样本（深度0 - 5厘米）。评估的参数包括总锰和有效锰以及其他微量元素、粒径、pH值、有机物含量和阳离子交换容量。基于401沿线的高交通密度，预计锰的沉积量会更高。在401和400巴里（E(+1)）站点之间未发现显著差异，这归因于锰的自然背景水平或其他来源（如富含锰的道路灰尘或天然地壳锰）对其的贡献。然而，400国王城（E(+2)）站点的锰含量明显低于其他三个站点，即401和400巴里站点。这可能是由401和400站点沿线的土壤类型所解释。发现400沿线的国王城站点的砂含量高于401站点。较高的砂含量可能导致锰向土壤底层的淋溶增加。尽管MMT在加拿大已持续使用约25年，但如本研究所示，其对陆地环境的贡献非常低，且未显著提高高速公路沿线的锰含量。
