Particulate total

The variation in total available sediment phosphorus concentration among the three sediment types shown in Table II is clear. A statistical analysis of this data shows that both the suspended sediment and particulate total phosphorus concentrations are greater than the bottom sediment value at the 99% confidence level. Phosphorus content increases in the sequence bottom sediment, suspended sediment, and particulate material in accordance with the increase in surface area (M. M. Reddy, New York State Dept, of Health, unpublished data, 1977). High surface area sediment components may adsorb phosphorus-containing substances,from the water column, increasing their phosphorus concentration. Another possible explanation includes dilution of bottom sediment by relatively inert primary minerals in the sand and silt size fractions. 

Typical results for Genesee River watershed bottom sediment phosphorus contents are (phosphorus analysis, x (ug/g), (ug/g), h) total phosphorus, 560, 140, 99 NaOH extractable phosphorus, 58, 62, 98 HCl extractable phosphorus, 398, 99, 98 NH20H extractable phosphorus, 74, 63, 98 (NH )2C204 extractable phosphorus 184, 93, 83. Bottom sediment, suspended sediment, and particulate total phosphorus (560 ug/g, 770 ug/g, and 910 ug/g respectively) Increase as does specific surface area, across these fractions indicating that adsorption processes may be important in increasing sediment phosphorus concentrations. 

Location Dissolved total Hg Particulate total Hg Dissolved reactive Hg Dissolved MMHg Particulate MMHg Dissolved DMHg Dissolved Hg° Reference(s)... 

Inhalation Total suspended particulates Total suspended particulates... 

Airborne Particulates Total suspended particulate matter found in the atmosphere as solid particles or liquid droplets. The chemical composition of particulates varies widely, depending on location and time of year. Airborne particulates include windblown dust, emissions from industrial process, smoke from burning of wood and coal, and exhaust of motor vehicles. 

Total airborne particulates are determined using a high-volume air sampler equipped with either cellulose fiber or glass fiber filters. Samples taken from urban environments require approximately 1 h of sampling time, but samples from rural environments require substantially longer times. 

The speciation scheme of Batley and Florence requires eight measurements on four samples. After removing insoluble particulates by filtration, the solution is analyzed for the concentration of anodic stripping voltammetry (ASV) labile metal and the total concentration of metal. A portion of the filtered solution is passed through an ion-exchange column, and the concentrations of ASV metal and total metal are determined. A second portion of the filtered solution is irradiated with UV light, and the concentrations of ASV metal... 

Environmental considerations also were reflected in coal production and consumption statistics, including regional production patterns and economic sector utilization characteristics. Average coal sulfur content, as produced, declined from 2.3% in 1973 to 1.6% in 1980 and 1.3% in 1990. Coal ash content declined similarly, from 13.1% in 1973 to 11.1% in 1980 and 9.9% in 1990. These numbers clearly reflect a trend toward utilization of coal that produces less SO2 and less flyash to capture. Emissions from coal in the 1990s were 14 x 10 t /yr of SO2 and 450 x 10 t /yr of particulates generated by coal combustion at electric utiUties. The total coal combustion emissions from all sources were only slightly higher than the emissions from electric utiUty coal utilization (6). 

Another ASTM test method. Potential Gum (D873), combines the existent gum and the oxidation stabihty tests to measure potential gum. A sample of gasoline is subjected to the oxidation stabihty test for 960 min, filtered to remove particulates, and then subjected to an existent gum test. The potential gum is expressed as the total (unwashed) gum in this test. 

Mg(OH)2 powder is classified by OSHA as a nuisance dust. ACGIH categorizes the powder form as particulates not otherwise classified. Exposure limits are as follows (108) ACGIH 10 mg/m , OSHA 5 mg/m (respirable), and 15 mg/m (total). Magnesium hydroxide is reported in the EPA TSCA inventory (109). 

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