Priority Existing Chemical

o.6Emergency procedures

Recommendations from the Ethyl Corporation Product Handling Guide for dealing with fire or spills of HiTEC 3062 consisting of 62% MMT in petroleum distillate (and applicable for the similar drummed MMT concentrates) state:

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  Personnel engaged in cleanup operations should be equipped with clothing and protective gear as suggested in the MSDS – chemical resistant gloves, suit and boots and safety glasses with side shields;
  
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  For minor spills, respirators must be worn; for significant spills, air-supplied respiratory equipment or self-contained breathing apparatus is required.
  

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  Use absorbent materials to remove free liquid from the spill area;
  
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  Clean smooth contaminated areas with a solvent, such as kerosene and collect rinsate with absorbent materials;
  
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  Remove contaminated soils and/or absorbents with appropriate tools such as shovels;
  
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  Thoroughly scrub smooth contaminated areas with soap and water.
  

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  Take immediate action to stop, contain and isolate the spill;
  
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  Eliminate all sources of ignition;
  
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  Barricade and restrict unauthorised personnel from the general area;
  
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  Notify regulatory authorities immediately in the event of imminent danger to human health or to the environment;
  
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  Contain spills with dykes or absorbent material to prevent migration and entry into sewers or streams;
  
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  Use water sprays to reduce vapours. Avoid flushing the liquid into a stream or an open sewer system. Blanketing the spill with high-density (low expansion type) foam is also effective to reduce evaporation. Commercial absorbents, activated charcoal, petroleum coke or fine soils can also be used to contain and collect the spill and reduce evaporation;
  
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  Pump all possible liquid from the spill area into steel closed-head drums or other suitable metal containers that can be sealed;
  
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  Finish collecting residual spilled material with absorbents. Remove contaminated soils and/or absorbents with appropriate tools and place in sealed metal containers or drums.
  

Use foam, water spray or dry chemicals to extinguish.

p)Discussion and Conclusions

With the national phase out of lead in petrol, there are now four types of AVSR additives presently marketed in Australia. MMT, phosphorus-based and sodium-based AVSRs are presently being assessed by NICNAS as Priority Existing Chemicals and a potassium-based AVSR was assessed by NICNAS as a New Industrial Chemical. These AVSRs are delivered either pre-blended into LRP or are available as an aftermarket fuel supplement for addition to unleaded fuel by consumers.

Due to commercial sensitivities of information on market share for individual AVSRs, exposure and risk assessments for each individual AVSR assume 100% market share. Additionally, given that the use of AVSRs is governed by a declining population of older vehicles requiring these fuel additives, risk assessments were conducted under two separate scenarios based on AVSR use patterns. The first scenario “Present Use” assumes a continuation of the present LRP market of 2500 ML per year with 90% of AVSRs delivered in bulk LRP and 10% delivered as aftermarket fuel additives. The second scenario “2004” assumes a decline of the LRP market to 1000 ML with the AVSR delivered totally as an aftermarket fuel additive. These scenarios are based on motor vehicle statistics and forecasts from the Australia Bureau of Statistics and Australian Institute of Petroleum. The occupational health and safety, public health and environmental consequences of these volumes and modes of delivery of AVSRs are considered accordingly.

MMT is manufactured overseas and assuming MMT has 100% of the AVSR market, less than 180 tonnes is being imported to Australia per year. The majority of this amount is used to blend LRP, with only a minor quantity (< 10 tonnes/year) used for the formulation of aftermarket fuel additives. Concentrated MMT (approximately 60% MMT w/w) is imported in bulk for formulation into LRP containing a recommended 72.6 mg MMT/L (approximately < 0.01% MMT w/w) and formulation of aftermarket products containing < 150 mg MMT/L (< 10% w/w MMT). A small amount is also imported in pre-packaged aftermarket products containing < 10% w/w MMT.

p.1Health hazards

MMT is acutely toxic by all routes of exposure. The critical effects from acute exposure to MMT are neurological and pulmonary dysfunction. In humans, giddiness, headache, nausea, chest tightness, dyspnea and paresthesia are reported in anecdotal cases of acute occupational exposure. Acute lethal exposure to MMT in animals is associated with damage to the lungs, kidney, liver and spleen effects, tremors, convulsions, dyspnea and weakness. In both animals and humans, slight skin and eye irritation results from dermal and ocular exposure respectively.

Limited data show that repeated inhalation exposure to MMT in animals results in degenerative changes in liver and kidneys. A NOAEL of 0.0062 mg/L for inhalation exposure was reported.

Manganese has been the subject of several extensive reviews and the summary of Mn toxicity for this present report is based predominantly on the WHO Concise International Chemical Assessment Document - Manganese and Its Compounds. In humans, Mn is an essential element. In animal studies, the critical effect following acute exposure to inorganic Mn compounds is neurological dysfunction. Decreased activity, alertness, muscle tone, touch response and respiration have been reported with oral administration. Pulmonary effects are also reported in inhalation studies, but these may at least in part reflect an inflammatory effect following inhalation of particulate matter rather than a result of pulmonary toxicity of Mn.

In repeated dose animal studies of Mn toxicity, the critical effect is also neurological dysfunction, and effects range from decreased motor activity to increased activity, aggression and movement tremors. In humans, chronic occupational exposure to respirable Mn dusts is associated with subclinical nervous system toxicity through to overt manganism, a progressive neurological disorder. Reproductive effects including impotence and loss of libido in male workers have also been associated with high Mn exposures.

It is generally agreed that the critical study for neurological effects due to Mn exposure is Roels et al., (1992). This principal neuroepidemiological study of occupational inhalation exposure to Mn was used by WHO (1999) to determine a dose-response relationship for neurological effects. A lower 95% confidence limit was estimated for the level of Mn exposure expected to result in a 5% response rate. This value (30 μg/m³) was considered a surrogate for a NOAEL for neurological effects in the present assessment.

MMT (as Mn) is currently listed in the NOHSC List of Designated Hazardous Substances (NOHSC, 1999b) with no classification. In accordance with the NOHSC Approved Criteria for Classifying Hazardous Substances (NOHSC, 1999a), It is recommended that MMT is classified “Hazardous” with the following risk phrases:

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  R26 - Very Toxic by Inhalation;
  
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  R28 – Very Toxic if Swallowed;
  
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  R24 – Toxic in Contact with Skin;
  
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  R48/23 – Toxic: Danger of Serious Damage to Health by Prolonged Exposure Through Inhalation.
  

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  S36 – Wear Suitable Protective Clothing;
  
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  S38 – In Case of Insufficient Ventilation Wear Suitable Respiratory Equipment.