Air Quality Standards for the Protection of Farm Animals from Fluorides

The ingestion of forages contaminated with inorganic fluorides from industrial sources constitutes an air pollution problem for domestic livestock. In cattle, which have been studied most extensively, the syndrome is characterized by dental and skeletal lesions, lameness, chemical evidence of increased fluoride ingestion, and in severe cases by effects on appetite and milk production. The only practical basis for a standard appears to be one based on forage fluoride concentrations. It is concluded that a standard should protect cattle from loss of milk production and from severe dental fluorosis, but need not be set so low that the animals will be protected against any discernible deviations from normal which do not influence their general health, productive ability, or the soundness and wearing quality of their dentition. As there may be wide seasonal variations in forage fluoride concentrations, the basic standard should be expressed as a yearly average of the forage fluoride concentration. However, as the developing teeth may be adversely influenced by short periods of high exposure, the standard should contain a provision which limits both the extent and duration of time that high concentrations may be tolerated even though they are balanced by lower values at other months. Based on these criteria, a tentative standard which limits forage fluoride to an average of 40 ppm, and limits the time that forage concentrations may exceed 60 or 80 ppm F is proposed.     

Effects of Inorganic Fluorides on Animals

Damage to animals by atmospheric fluoride pollution involves only those animals who subsequently graze on contaminated forages. The chronic disease which results has been most extensively studied in cattle, where the general symptoms are: A n interference with normal dentition, development of osseous lesions, and a diminished appetite which may lead to weight loss or decreased milk production. Studies completed to date would indicate that depending on the conditions of exposure the tolerance level for dairy cattle is about 1.3 mg F/kg (40 ppm F in diet). Because the route of exposure is via the forage, it would seem unreasonable to base any control standard on atmospheric fluoride levels. The forage fluoride levels, analytical evidence from the animal, or even some early sign of fluoride ingestion on the animal might form a more logical basis for a standard.     

Elemental Uptake by Seaweed,Plocamium corallorhirza Along the KwaZulu-Natal Coast of Indian Ocean,South Africa

This study reports the elemental uptake by Plocamium corallorhiza, a Rhodophyta class of coralline alga grown richly along KwaZulu-Natal coastline. The uptake of seven important elements, namely Fe, Mn, As, B, Ti, Zn and Hg, selected based on their abundance in the samples, were investigated for a one-year cycle, from June 2002 to May 2003, at four chosen sites located along the KwaZulu-Natal coastline. The sites spread over 150 km from North to South Coast are Zinkwasi, Ballito, Treasure Beach and Park Rynie. P. corallorhiza possess good manganese and arsenic-accumulating ability and has potential to be an excellent indicator for most of the metals studied. A typical P. corallorhiza sample at Park Rynie (winter) recorded Mn (14 ppm), Fe (6.02 ppm), As (8.4 ppm), B (1580 ppb), Zn (234 ppb), Ti (751 ppb) and Hg (15.8 ppb). The general trend found at all sites was a large decrease in iron concentration in spring and summer and increase in winter. Mercury uptake was lowest in winter and autumn at all sites. The highest mercury levels in the seaweeds were recorded during spring or summer.     

Occurrence of dioxins in cow's milk in the vicinity of municipal waste incinerators and a metal reclamation plant in the Netherlands

Over 200 samples of cow's milk have been analysed for dioxins in a survey on the occurrence of dioxins in milk from the vicinity of municipal waste incinerators (MSWs) and other potential dioxin sources in The Netherlands. Levels in milk were found to vary considerably with time, depending on emission rates, the direction and distance to the source and the feeding and housing of cows. Highest levels of up to 13.5 pg TEQ/g of milk fat were found in the Lickebaert area and Zaandam near two incinerators with highest emission rates. The background level ranged between 0.7 and 2.5 pg TEQ/g of milk fat. Levels in winter were comparable to those found in summer and, in some areas, even higher, when cows were fed with hay and silage harvested on the same farm. After the closure of the MSW in Zaandam, cow's milk from neighbouring farms showed a significant decrease in dioxin levels to below the critical limit of 6 pg TEQ/g of milk fat. Dioxin levels in the vicinity of a metal reclamation plant were comparable to those in milk from the vicinity of a MSW with moderate emissions. Differences were observed in the ratio PCDF/PCDD, which was higher in milk near the metal reclamation plant. Principal component analysis has been applied on a large data set of patterns of the 2,3,7,8-chlorine substituted PCDDs and PCDFs in cow's milk. This technique has proved to be useful for distinguishing and identification of sources on the basis of the isomer pattern in milk.     

Residues of lindane and its metabolites in eggs, chicks, and body tissues of hen pheasants after ingestion of lindane-14C via treated wheat seed or gelatin capsules.

Studies were carried out to investigate possible contamination of pheasants with residues of lindane used as seed dressings for the control of wireworms in cereal crops. One group of laying hen pheasants was fed 20 mg of lindane-14C in gelatin capsules while another group was fed wheat seed treated with 100 ppm of lindane-14C for 15 days. Residues in eggs were monitored for about 70 days. Residues in chicks hatched from the eggs were also measured. Concentrations of residues in muscle, liver, brain, and fatty tissues were determined at various times. 14C-labeled residues in eggs increased sharply in the capsule treated group and reached an average maximum of about 19 ppm in 8 days. This level decreased to less than 0.5 ppm in about 50 days. Residues in eggs from the pheasants fed treated seed increased gradually to an average maximum of 17 ppm 22 days after commencement of the feeding program. This level decreased to less than 0.5 ppm 50 days later. Residues in hatched chicks were significantly lower than those in the eggs. Highest concentrations of residues were found in fatty tissues which decreased to non-detectable level in 6 months. Several chlorobenzene metabolites were identified in egg yolk and chick tissues. Chlorophenolic metabolites were indicated only in chicks.     

Deltamethrin residues in milk and tissues of lactating dairy cows.

Lactating dairy cows were fed deltamethrin (2 or 10 mg kg-1 feed) for 28 consecutive days and deltamethrin residues measured in milk and tissues. Deltamethrin residues were higher relative to dose administered. The order of relative concentrations of deltamethrin in tissues, measured 1, 4, and 9 days after the last dose was: renal fat greater than subcutaneous fat greater than forequarter muscle greater than hindquarter muscle greater than liver greater than kidney. Depletion of deltamethrin residues in milk was very rapid indicating the half-life of the insectide of about 1 day. Trace amounts of deltamethrin metabolites 3-(2,2-dibromovinyl)-2,2-dimethylcyclopropane carboxylic acid (less than 0.0235 ppm) and 3-phenoxybenzoic acid (less than 0.034 ppm) were also detected in milk and tissues of treated cows.     

Biological evaluation of SZI‐121, a new miticide

Abstract

A large number of tetrazine analogues were synthetised and tested as miticides. A comprehensive screening system was applied to recognise some effects important in terms of field performance. A promising new substance, coded as SZI‐121 was choosen for further development. It proved to be about four‐times more active as an ovicide (LC₅₀=0.05 ppm) than the reference clofentezine, when administered to the eggs directly (LC₅₀=0.23 ppm). In contrast to clofentezine which has solely a contact mode of action, SZI‐121 has excelent translaminar activity acting on already laid eggs (LC₅₀= 18.66 ppm) or those in females feeding on the opposite, non‐treated side of the leaf (LC₅₀=5.11 ppm). High toxicity of SZI‐121 to the chrysalis form (LC₅₀=0.39 ppm) was also observed. The field rate of SZI‐121 is 60–100 g a.i./ha against a wide range of phytophagous mites including European red mite (Panonychus ulmi), two spotted spider mite (Tetranychus urticae), grape leaf rust mite (Calepitrimerus vitis), vine leaf blister mite (Colomerus vitis), apple leaf rust mite (Aculus schlechtendali), stone fruit leaf rust mite (Vasates fockeui). Because it stops the development of mites in egg and chrysalis forms simultaneously, SZI‐121 can be used independently from actual development stages of mites during the whole season as the field trials demonstrated. These characteristics permit SZI‐121 to be easily fitted into integrated pest management.     

Elevation of intracellular free calcium levels in sperm in response to long-term feeding of fungicides to mice.

To assess the impact of long-term feeding of fungicides on sperm quality, mice were fed a daily diet containing a mixture of maneb and zineb, at concentrations of 30, 300, and 3000 ppm, respectively. Employing epididymal sperm suspended in a medium permitting in vitro capacitation, the intracellular free Ca2+ concentration, [Ca2+]i, was determined with a fluorescent Ca2+ indicator, Fura-2. Regardless of the fungicide dosages applied, [Ca2+]i was about 50 percent higher in treated animals relative to a value of 123 nM [Ca2+]i in the control group. Fungicide-treated mice were mated to mature, non-treated females; as in the control, the litter sizes were the same. In conclusion, the observed elevation in [Ca2+]i seems to reflect cellular adaptation responses to toxic stress at moderate fungicide doses.     

Comparison of PCDD/PCDF levels in soil, grass, cow''s milk, human blood and spruce needles in an area of PCDD/PCDF contamination through emissions from a metal reclamation plant

When in the vicinity of a metal reclamation plant in Tyrol, Austria, increased PCDD/PCDF levels were found in soil and spruce needles, the extent of grass contamination as well as the PCDD/PCDF content in milk of cows fed with hay from this area was determined. The milk samples showed a significant increase in PCDD/PCDF levels compared to control samples. In a blood sample of a farmer a significant increase in PCDD/PCDF levels was found. Correlations in PCDD/PCDF levels between soil, spruce needles, grass, cow's milk and human blood will be presented.     

Azadirachtin induced changes in feeding,dietary utilization and midgut carboxylesterase activity of the final instar larvae of spodoptera litura (fabricius) (lepidoptera: Noctuidae)

Abstract

Final (sixth) instar larvae of Spodoptera litura were fed in increasing amounts of azadirachtin and the effects on feeding activity, dietary utilization and mid‐gut carboxylesterase activity were determined. The antifeedant activity of azadirachtin did not increase in a dose‐dependent manner as reflected by the decline in antifeedant effect at higher doses of 30 and 50 ppm. Dietary concentrations of azadirachtin although significantly lowered the efficiencies of conversion of both ingested (ECI) and digested (ECD) food, it failed to lower the approximate digestibility (AD). The latter however, increased significantly with increasing concentrations of azadirachtin. Feeding of higher doses (30 and 50 ppm) resulted in significant increase in midgut carboxylesterase activity. Thus insensitivity to antifeedant effects and induction of midgut carboxyesterase activity in the older larvae of S.litura In response to high doses of azadirachtin observed in this study can have adverse consequences unless particular attention is paid in developing application strategies for azadirachtin based biopesticides for use in pest control protocols.     

Effect of maternal dietary hexachlorocyclohexane exposure on pup survival and growth in albino rats

Abstract

In adult albino rats, maternal dietary. ß‐ and ?‐hexachlorocyclohexane (HCH) intake during gestation upto 400 ppm level did not affect the number of litters produced. But about 50 and 100% pup mortality was found in 200 and 400 ppm ß ‐HCH group within 5 days of birth. Maternal mortality was observed in 800 ppm ß ‐HCH group during third week of gestation. The effect of maternal dietary intake of HCH isomers at 50 and 250 ppm level during gestation and/or lactation on perinatal development was also studied. The body weights and sizes of the newborn litters of mother rats exposed to dietary HCH isomers did not. differ from controls. Similarly, the growth and development of the litters of HCH exposed mother rats that survived 28 day lactation period were found to be comparable to controls as evidenced by the body weight and weight of vital organs. However, liver weight increases were found in the 28 day weaned litters wherever the mothers had been exposed to HCH isomers during lactation. Lowered kidney weight was seen in litters of mother rats fed 250 ppm ?‐HCH during gestation and lactation. The brain and testis weights were not affected in the litters of any experimental groups.     

Reproduction of mallards following overwinter exposure to selenium

Forty pairs of mallards (Anas platyrhynchos) were fed 15 ppm selenium as selenomethionine for about 21 weeks during winter. Twenty pairs served as controls. At the end of 21 weeks, which coincided with the onset of the reproductive season, selenium treatment was ended. Four birds died while on selenium treatment. Treated females lost weight, and their egg-laying was delayed. Hatching success of some of the first eggs laid by selenium-treated females was lower than that of controls, and a few of these early eggs contained deformed embryos, but, after a period of about two weeks off the selenium-treated diet, reproductive success returned to a level comparable with that of controls. The return to normal reproductive success was the result of a corresponding decrease in selenium concentrations in eggs once selenium treatment ended.     

Analysis of air quality in Dire Dawa,Ethiopia

Ambient air quality was monitored and analyzed to develop air quality index and its implications for livability and climate change in Dire Dawa, Ethiopia. Using survey research design, 16 georeferenced locations, representing different land uses, were randomly selected and assessed for sulfur dioxide (SO₂), nitrogen dioxide (NO₂), carbon dioxide (CO₂), carbon monoxide (CO),volatile organic compounds (VOCs), and meteorological parameters (temperature and relative humidity). The study found mean concentrations across all land uses for SO₂ of 0.37 ± 0.08 ppm, NO₂ of 0.13 ± 0.17 ppm, CO₂ of 465.65 ± 28.63 ppm, CO of 3.35 ± 2.04 ppm, and VOCs of 1850.67 ± 402 ppm. An air quality index indicated that ambient air quality for SO₂ was very poor, NO₂ ranged from moderate to very poor, whereas CO rating was moderate. Significant positive correlations existed between temperature and NO₂, CO₂, and CO and between humidity and VOCs. Significant relationships were also recorded between CO₂ and NO₂ and between CO and CO₂. Poor urban planning, inadequate pollution control measure, and weak capacity to monitor air quality have implications for energy usage, air quality, and local meteorological parameters, with subsequent feedback into global climate change. Implementation of programs to monitor and control emissions in order to reduce air pollution will provide health, economic, and environmental benefits to the city.

Implications: The need to develop and implement emission control programs to reduce air pollution in Dire Dawa City is urgent. This will provide enormous economic, health, and environmental benefits. It is expected that economic effects of air quality improvement will offset the expenditures for pollution control. Also, strategies that focus on air quality and climate change present a unique opportunity to engage different stakeholders in providing inclusive and sustainable development agenda for Dire Dawa.     

Response of Tomato Fruiting to Hydrogen Fluoride as Influenced by Calcium Nutrition

Two varieties of tomatoes grown at 40 to 200 ppm calcium were continuously fumigated with HF throughout flowering and fruit development. Fruit size was directly related to the level of calcium nutrition, and within each calcium treatment the fruits on plants subjected to HF at about 6 μg F/m³ were smaller than those on unfumigated plants. The smaller fruit size was associated with partial or complete seedlessness, suggesting that calcium plays an essential role in fertilization with which fluoride may interfere. Fluoride injury to the tomato foliage was most severe at the lowest calcium level. Treatment with HF at about 8 μg F/m³ produced some injury to tomato foliage but had no apparent effect on fruiting. Evidently fluoride can affect plant fruiting, but considering the severity of the HF treatments required, effects on tomato fruiting probably are of little practical significance. The relationship between fluoride injury and calcium nutrition suggests interference with calcium metabolism as a mechanism of fluoride injury to plants.     

平板炭气凝胶电极电吸附除氟

采用自制的炭气凝胶平板电极进行模拟水样中氟的电吸附去除研究,通过单因子实验优化了该电吸附技术的操作参数和适用的溶液条件,并研究了反接电极法的再生效果。研究结果表明,自制的炭气凝胶平板由纳米颗粒组成三维网络结构,比表面积为670.90 m2/g,具有良好的充放电可逆性和迅速形成表面双电层的特点。静态电吸附除氟效果最佳的条件为:水样氟离子浓度6 mg/L,pH 7.0,极板间距4 cm,电压1.6 V;共存物质硝酸根、腐殖酸、碳酸根和碳酸氢根等对氟离子的电吸附具有一定的促进作用。吸附氟离子后的炭气凝胶材料的比表面、孔体积、电容值有所减小。对于吸附氟离子后的炭气凝胶平板电极,采用反接电极法取得较好再生效果的条件为:流动状态、电压1.6 V、极板间距4 cm。再生后的炭气凝胶电极与原始炭气凝胶相比,依然具有良好的充放电可逆性。     

Variability of Ozone Air Quality Indicators in Selected Metropolitan Statistical Areas

This article analyzes numerical variability In ozone air quality data to understand how this variability affects the number of violations seen each year in metropolitan statistical areas (MSAs). Three commonly cited violation indices are used: 1) the annual number of expected exceedances averaged over 3 years is greater than 1; 2) the n+ 1th hourly value in n years of data is greater than 0.12 ppm; and 3) the annual number of expected exceedances is greater than 1. Only the first index is consistent with applicable regulations. The analyses indicate that about 23 percent of all MSAs with valid data had one or more change In their ozone violation status between 1979 and 1987. This change in status occurred for approximately 7 percent of all MSA-years of available data. This statistic was about one-third of the value usually obtained when the two incorrect, but commonly used, criteria of ozone violations are used.     

氟石膏中氟的分布及固氟脱酸改性

以工业副产物氟石膏为研究对象,通过筛分进行粒度分析,得到不同粒径pH值、水溶性氟以及总氟含量的变化规律;重点研究了掺入2种碱性工业副产物作为改性剂对氟石膏化学改性固氟脱酸的效果,从而确定改性剂的最佳掺量。结果表明,氟石膏中氟的分布有一定规律;掺加5%的电厂干法脱硫灰或2%钢铁厂烧结烟气脱硫灰能很好的起到固氟脱酸的效果。     

Comparison of the effects of seleno-L-methionine, seleno-DL-methionine, and selenized yeast on reproduction of mallards

The toxicities of seleno-L-methionine, seleno-DL-methionine, and selenized yeast were compared. Ten pairs of mallards were fed a control diet and 15 pairs were fed diets containing 10 ppm selenium as seleno-DL-methionine, seleno-L-methionine, or selenized yeast. Hatching of fertile eggs was significantly lower for females fed 10 ppm selenium as seleno-DL-methionine (7.6%) and seleno-L-methionine (6.4%) than for controls (41.3%). Survival of ducklings was lower when their parents had been fed 10 ppm selenium as seleno-L-methionine (20.0%) than for controls (98.4%). The number of 6-day-old ducklings produced per female was significantly lower for mallards fed 10 ppm selenium as seleno-DL-methionine (0.47) or selenized yeast (2.67) than for controls (6.10), and was significantly lower for mallards fed seleno-L-methionine (0.13) than for mallards fed selenized yeast. The eighth eggs of females fed the DL or L forms of selenomethionine contained means of 9.2 and 8.9 ppm selenium, wet weight; these means were higher than the mean (6.6 ppm) for females fed selenized yeast. Among embryos that died at 7 days of age or older, the percentage of embryos that were deformed was 1.3% for controls, 24.6% for seleno-DL-methionine, 28.2% for seleno-L-methionine, and 11.0% for selenized yeast. The results suggested that seleno-DL-methionine and seleno-L-methionine were of similar toxicity and were both more toxic than selenium from selenized yeast.     

Air Quality Criteria for the Effects of Fluorides On Man

Minute traces of fluoride are found in the air of rural communities and of cities, having been contributed perhaps from volcanic effluvia, perhaps from burning coal, and perhaps from industrial sources. Atmospheres of urban areas of the U. S. have been found to contain from less than 0.2 μg F/m³ to as much as 1.9/μg F/m³. Fluorides released from industrial processes may release elemental fluorine, soluble gaseous fluorides, and soluble or insoluble fluoride dusts. At least in some instances inhaled fluoride from fluoride containing dusts has proven to be as biologically available as that from similar concentrations of inhaled HF. Measurement of the amount of fluoride excreted in the urine has proven to be a valuable index of exposure and a means of preventing cumulative injury. Average urinary F concentrations not exceeding 5 mg/liter, which corresponds approximately to a daily intake of 5 mg, are not associated with osteosclerosis in such workmen, and such changes are unlikely at daily intakes of 5 – 8 mg F. The amount of fluoride which is retained by an individual inhaling air containing 2.5 mg of fluoride dusts per m³ (the current TLV) is approximately 5-6 mg. A review of the literature describing the exposure of work forces to fluorides in industrial atmospheres indicates that concentrations have ranged from a fraction of a milligram/m³ to values mostly less than 10 mg/ml Surveys of populations living near installations emitting fluoride fumes or dusts indicate that, with few exceptions, the health of these persons has not been adversely affected. Many species of vegetation are far more susceptible to the effects of fluoride than is man, hence an air quality standard to protect vegetation will be far lower than those encountered in the factory, and can be expected to be of the order of 10 ppb or less. The probable daily intake of F at this level of exposure is 0.16 mg, an intake far below that required for the production of clear-cut effects in the human. Thus, air quality standards set to protect vegetation would contribute negligible quantities of F in terms of any possible adverse effect on human health, and would give a wide margin of protection for man.     

Effect of squalane on hexachlorobenzene (HCB) concentrations in tissues of mice

Abstract

Female mice were given 100 mg HCB/kg body weight i.p. and fed diets containing 0, 2.5, 5.0, and 7.5% of squalane. After 3 weeks samples of livar, blood and abdominal fat ware analysed for HCB as well as for squalane. HCB concentrations were significantly lowered as comoared to controls in all tissues and at all dietary concentrations of squalane to a maximum of about 36% in fat, 44% in liver and 47% in blood. The effect of squalane upon HCB concentrations was strongly dose depedent in abdominal fat. In contrast, no significant differences were seen with liver and blood between animals fed 5.0 or 7.5% of squalane. Squalane was detected in considerable amounts in the livers (50–100 ppm) but r.ct in abdominal fat (<1 ppm) of mice fed squalane.