Laserfiche WebLink
Spectrum Laboratories Chemical Fact Sheet-Cas#71432 http://www speclab torr,/compound/c92527 <br /> t <br /> with a 7md speed of 7 09 misec was 5 23 hrs ,the estimated half-Irfe for <br /> tilization ofbenzeae from amaodel river one meter deep flowing I msec with a <br /> wind velocity of 3 msec is estimated to be 2 7 hrs at 20 deg C It win not be <br /> expected to significantly adsorb to sediment,bioconcentrate in aquatic organisms or <br /> hydrolyze It may be subject to biodegradation based on a reported biodegradation <br />' half-life of 16 days in an aerobic river die-away test In a marine ecosystem, <br /> biodegradation occurred in 2 days after an acclimation period of 2 days and 2 weeks <br /> Environmental Fate in the summer and spring,respectively,whereas no degradation occurred in winter <br />' AQUATIC FATE Evaporation was the primary loss mechanism in winter in a <br /> Ynesoco,m experiment which simulated a northern bay where the half-life was 13 <br /> days In spring and summer the half-lives were 23 and 3 1 days,respectively In <br /> these cases biodegradation plays a major role and takes about 2 days However, f <br />' acclimation is critical and this takes much longer in the colder water in spring <br /> According to one experunent,benzene has a half-life of 17 days due to <br /> Iphotegradationwluch could contribute to benzene's removal In situations of cold <br /> water,poor nutrients,or other conditions less conducive to microbial,photolysis <br /> J will play a important role in degradation ATMOSPHERIC FATE If benzene is <br /> i released to the atmosphere, it will exist predominantly in the vapor phase <br /> Gas-phase benzene will not be subject to direct photolysis but it will react with <br /> photochemically produced hydroxyl radicals with a half-life of 13 4 days calculated <br /> using an experimental rate constant foi the reaction.The reaction time in polluted <br /> atmospheres which contain nitrogen oxides or sulfur dioxide is accelerated with the <br /> �half Iife being reported as 4-6 hours Products of photoomdation include phenol, <br /> nitrophenols,nitrobenzene,formic acid,and peioxyacetyl nitrate Benzene is faiily <br /> soluble in water and is removed fa-orn the atmosphere in rain <br /> DRINKING WATER 113 public-'sup lies, 1976,7 s_ites poi,avg of positive sites <br /> 5 USA cities, 1974-5,0-0 3 ppb Contaminated drinking water wells in <br /> INY,NJ,CT,30-300 ppb,highest conn in drinking water from surface soul ce,4 4 <br /> ppb 3 surveys of community water supplies 0 of 11 I pos, 7 of 1 13 pos,mean 4 <br /> ppb,4 of 16 pos(0 95 ppb-max) USA Groundwater Supply Survey(GWS, 1982, 1 <br /> finished drinking water),466 samples selected at random from 1000 in survey, <br /> 0 6%pos,3 ppb median, 15 ppb max Wisconsin drinking water wells,data <br /> through Jun 1984, 1174 community wells,0 34%pos,617 private weIIs,2 9% <br /> ' pos(6) GROUNDWATER Chalk Aquifei (UK),210 m from petrol storage, 1-10 <br /> ppb,Chalk Aquifer(UK), 120 in from petrol storage,>250 ppb,Chalk Aquifer f <br /> (UK), 10 in from petrol storage, 1250 ppb, distances refer to benzene movement Tri <br /> groundwater SURFACE WATER 14 heavily industrialized with basins, ' <br /> ' 1975-1976,20%samples>1 ppb and between I and 7 ppb Lake Erie, 1975-6,0-1 <br /> ppb, I of 2 sites positive,Lake Michigan, 1975-6, 0-7 ppb, 5 of 7 sites positive i <br /> 700 random sites in US, 1975, 5 4 ppb'avg US EPA STORET database, 1,271 <br /> samples, IS 0%pos, 5 0 ppb median SEAWATER 5 15 parts Pei trillion Gulf of <br /> `Mexico, 1977,unpolluted areas, 5-175 parts per trillion,Gulf of Mexico, 1977, <br /> anthropogenic influence RAIN/SNOW Detected in rainwater in Japan and m the <br /> UK(87 2 ppb)(1,2) Benzene occurs in both ground water and surface public water <br /> supplies with higher levels occurring in b oundwater supplies Based upon Federal <br /> drinking water surveys, approximately 1 3%of all ground water systems are <br /> estimated to contain benzene at levan;greater than 0 5 ug/I The highest level <br /> reported in the surveys foi ground water was 80 ug/1 Approxnnately 3%of all 4 <br /> ' surface water system are estimated to be contaminated at levels higher than 0 5 ug/I <br /> None of the systems are expected to contain levels lugher than 5 ug/1 EFFL <br /> Wastewater from coal preparation plants, 0 3-48 ppb, wastewater from plants which � <br /> ' ;manufacture or use benzene<1-179 parts per tnllron, stack emissions from coking <br /> plants (Czechoslovakia), 15-50 ppm ,stack emission estimates from chemical plants <br /> 1 fusing emissions and worst case modeling at 150 in from source,less than oi, equal to <br /> Drinking Water Impact ;5 ppm Groundwater at 178 CERCLA hazardous waste sites, 112%pas US EPA I <br /> fSTORET database, 1,474 samples, 16 4%pos,2 50 ppb median Industries in <br /> which mean or max levels in raw wastewater exceeded I ppin are(number of <br /> (samples,percent pos,mean,max,in ppm) law wastewater auto and other laundries <br /> I 1(20 samples, 70%pos,<1 4 ppm mean,23 ppm max),iron and steal manufacturing <br /> (mfg)(9 samples,77 8%pos,<8 0 meati,46 max),aluminum fonrimg(32 samples, <br /> 3of4 <br /> nr�ti nrinriq a i i <br /> 1 <br />