JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY
Year:2004 | Volume:- | Issue:20|Papers Count:9

The toxic effects of Saturn 50% (Herbiside) and Malation 57% (Insectside) were studied on Persian sturgeon (Acipenser persicus) fingerling weighting 1-3g in 2003. The acute toxiciy of Saturn and Malation on the mortality of Persian sturgeon was studied in order to determine the LC50 96h. The experiments were carried out on the basis of standard methods in static state.The PH and total hardness of the water determined throughout the experiment that were 6.5 - 7 and 23mg/l, respectively. The water temperature was 25±1°c and dissolved oxygen values were higher than 7mg/l.On the basis of the results obtained, LC50 96h of Saturn and Malation on Persian sturgeon fingerlings was 0.007 and 10mg/l, respectively.The maximum permissible concentration for Saturn Malation on Persian sturgeon fingerlings were 0.0007 and 1mg/l, respectively. Therefore on the basis of standard the pesticide Saturn is considered highly toxic and Malation, medium toxic/or the fingerlings under study.

Urban runoff has a large rate of various pollutants and destroys acceptor water resources and also damage environment. The management strategies for urban runoff pollutants controlling depend on identifying and analyzing these pollutants. In this study the procedure for fitting, selecting and appropriate probability distribution function (pdf) for a runoff quality constituent concentration in Isfahan was investigated. The best fitted probable distribution of pollutants concentration was determined and it was used for estimation of concentrations with different return periods. The gtimated pollutant concentration with different return periods is using Selected pdf The results showed BOD5 and COD can be modeled by Gamma distribution, and TSS, No3, TP, Ph are statistically fitted with 2 lognormal distribution. Also, pollutant concentrations were increased with return period.

The objective of this study is to calculate the amount of Tehran air pollution due to motorcycles traffic via modeling and field survey. The first step to achieve motorcycles, daily traffic and average velocity. A relevant questionnaire designed and with field survey method, distribution of Motorcycles (4-stroke, moped), kind of usage, estimate of mileage and average velocity gathered. The data has been compared with traffic data, manufacturing statistics and the latest study in this field. Finally With the obtained data and emission factor for each kind of motorcycle a new model was developed based on the emission inventory models. Annual emission for Tehran motorcycles was calculated. The contribution of mobile sources and motorcycles has been estimated by the developed model. The results showed that in 2002 the number of active motorcycles in Tehran was 450,000 the contribution of environment pollutants from these mobile sources was %21 and %9 for co and PM 10 and there has been about, 450000 active monocles (58% 4-stroke, 28% 2-stroke, 14% moped) 1% and 44% for Nox and NMVOC. The contribution of motorcycles among mobile sources in Tehran air pollution was estimated %22.

Nowadays, industrial waste waters consider as basic anxiety in all countries specially in developing and industrial wastes are the most environmental pollutants. There are many types of compounds in the industrial waste waters and heavy metals are considered as the most pollutants.Chemical etching is a controlled corrosion process that is capable of maintaining tolorances of 1/1000 inch. Chemical etchant solutions have finite lifespans due to gradual, international contamination. When steel alloys are etched, the chief contaminants are heavy metals and iron, specially: Cd(II), Ni(II), Pb(II), Zn(II), Cr(II.III). In his Study selective removal of heavy metals investigated using sodium sulfide and ferric solfide. Last usages of mentioned compounds in heavy metals removal showed that the effect of removal is maximum. In pH range approximately 5 to 10 but the results of this study showed that heavy metals precipitation can be accomplished in pH range 0 to 1. According to the results obtained sodium sulfide affects better than other compounds and optimum concentration rate is 1 mol sodium sulfide per 1 mol non-ferros metals. Removal percent of Cd, Zn, and Fe(II) using above mentioned rate of sodium sulfide is 62.9%, 7.89%, 53.44%. 15.89%, respectively. According to the results, iron recovery percentage is low and the treated ferric chloride solution can be reused.

Tehran as the capital of Iran has so many attractions which have resulted in problems such as industries centralization and increasing population in and around the city. Therefore, water demande has become ever increasing. It is important to notice that discharging untreated domestic and industrial wastewater into the groundwater has resulted in much pollution and raising there round water level. On the other hand, in recent years there was decreasing rainfall and so water shortage has been obvious. Therefore it seems an essential task to reuse and or recycle water in present industries.In this study and among the established industries in Tehran, factories having fifty or more workers of textile, tannery, pulp and paper industries have been selected as the sample group. Most of the tanneries were transferred from Tehran city to the outside about 14.5% of total remained industries are related to textile, Pulp and paper manufacturing in the first phase of this study. The qualitative and quantitative characteristics of water used in these factories and possibilities for water recoiling have been investigated.The results of study showed that the most consumption is related to textile industry. Water needed/or all selected industries was brought about from tap water (11%), tap water and deep weels (11%) and deep weels (78%).The amount of' waste water produced by textile. Wood pulp and paper and trains in Tehran area was about 21500m3 and considering 200 liters per capital of wastewater production, it would be equivalent to 107500 persons per day wastewater production.

The objective of this study is to investigate the geographical distribution of ticks in the Boyerahmad city. Survey occurred in the 1/10 of villages in this city. Ticks were collected of different places including plain high land, highland- plain in different seasons. 2173 ticks (soft, hard) were totally collected that 820 were soft ticks (Argasidae family) and 1353 were among hard ones (Igsodideh). Argas and ornithodorus were recognized among soft ticks. Argas genius has two species A. persicus %23.92 and A. reflexes %2.50, and genera ornithodorus only one species O.lahorensis %11.32. Amongst hard ticks 3 genous and 7 species identified as. follow: Haemaphysalis genous (Hae sulcata %27, 75. Hae conceinae %0.43) Hyabma (Hy scholzei %8.51, Hy marginatum % 4.80, Hy deteritum % 4.80). Rhepicephalus genus (Rh bursa %3.81, Rh Sanginus % 0.55) in the soft ticks A. persicus and in the hard ticks Hae sulcata were the main species, respectively. These were collected from animal shelters, find nests, animal bodies and human house.