Characterisation of cobalt‐binding proteins in occupational cobalt exposuret†

In animal experimentations cobalt is found to be carcinogenic under conditions which are comparable with a possible exposure of human beings at the workplace.^1,2 Little is known about binding and distribution of incorporated cobalt in blood.

Blood, serum and plasma of workers occupationally exposed to cobalt were analyzed concerning cobalt‐binding. The samples were focused by preparative IEF in layers of granulated gels. The cobalt concentrations in the isolated fractions were measured with the aid of flameless atomic absorption spectrometry. The whole blood samples exhibit peaks with different sizes in the pH‐5‐ and ‐7‐range. The proportion of these peaks can change with individual samples. In serum and plasma cobalt is found only in the pH‐5‐range.

When separated by gelelectrophoresis under denaturating conditions the cobalt‐fractions in all blood, serum and plasma samples shows a similar protein pattern. Several proteins with different molecular weights are detected in the pH‐5‐fractions, whereas only hemoglobin is found in the pH‐7‐fractions. In agreement with these results is the refocusing in ultrathin‐layer of polyacrylamide. Heterogeneous protein patterns are demonstrated with the pH‐5‐fractions; the pH‐7‐fractions yield only the hemoglobin pattern.

In vivo cobalt is bound to plasma proteins‐perhaps‐albumin^3,4‐and hemoglobin. Till now the chemical structure of the binding is unknown.     

Clinical and analytical follow‐up of 25 persons exposed accidentally to beryllium†

An accidental exposition of 25 persons to beryllium dust was used to follow up trace analytical and clinical parameters over a period of 10 months. Although no exposed person shows any symptoms of an acute beryllium intoxication, up to 5‐fold increased beryllium concentrations could be analysed in serum samples about 10 hours after exposition. The beryllium clearance shows a biological half time in the range of 2 to 8 weeks. The beryllium determination in the nanogram range was carried out using a combined method by flameless a.a.s. with a detection limit of 0.6 ppb Be and a relative standard deviation from 20 to 4% in relation to the concentration range of beryllium measurement.

Beryllium analyses are completed by thorax X‐ray, spirometry, y‐globulins and liver enzymes (SGOT, SGPT), which have shown no pathological values. Because it is known for beryllium to sensitize the cellular immune response, neopterin measurement was used to determine the activity of the immune system. Neopterin, a pteridine synthesized by activated macrophages after stimulation by gamma‐interferon derived from sensitized T‐lymphocytes, was determined in urine samples by HPLC combined with an fluorescence detector. Only in two cases a slight increase of neopterin has been found. As a result of this study it can be summarized, that a short‐time exposure to beryllium (10–20 h), which results in a increase of beryllium in serum to the fivefold normal beryllium level, does not initiate any symptoms of an acute beryllium intoxication. The exposed persons are controlled in future to evaluate the further course.     

Controlling pollution from land‐based sources in the Turkish Mediterranean coast—legislative aspects

The Turkish Mediterranean Coast is still the cleanest section in the region. This aspect needs to be strictly controlled and improved to allow for a sound development of touristic activities. Also, the adopted controlling policy should comply with the basic principles of the Mediterranean Action Plan. In Turkey, the regulations issued in connection with the “Water Products Law”; are now implemented to control wastewater discharges. Recently, major efforts were devoted to improve these regulations within the umbrella of the new “Environmental Law”;. The new proposals consider the issue from a much broader framework and provide technical support and criteria for marine outfalls, direct discharges of domestic and industrial sources and pretreatment requirement prior to discharge to the sewerage systems.     

Humic substances. Part III. sorptive interactions with environmental chemicals†

The formation of covalent binding to DNA of a carcinogen is now widely accepted to represent a classical mechanism of tumour induction in mammals. This mechanism does not operate with metals since no covalent binding of these agents to DNA does occur. Nevertheless, somatic mutations as typical consequences of DNA‐damage have been reported to be induced by metals in various model systems. Beside DNA‐alkylation such damages can be caused by changes in the conformation of DNA or in the fidelity of DNA‐repair. The activity of the repair enzymes DNA‐polymerases is indeed impaired by many metal ions at least in vitro. It is not yet established whether these mechanisms are also important in the intact mammalian organism. Much evidence has accumulated during the last years that a disturbance of the balance of cations and especially metal ions represents another possible mechanism of tumour induction. The tumours found with high doses of chelating agents such as nitrilo‐triacetic acid (NTA) have to be discussed in this context. Since most—if not—all of the speculative mechanisms of metal carcinogenesis resemble classical pharmacological reactions the existence of a threshold level is likely. So metal carcinogenesis will not be a problem of the environmental contamination at trace levels but a problem of occupational medicine.     

Dissipation of fluvalinate and characterisation of its degradation products on chickpea crop by mass spectroscopy

Fluvalinate was applied on chickpea crop at (i) 0.056, (ii) 0.112 and (iii) 0.56 kg a.i. ha^‐1 to evaluate its rate of dissipation. Two major degradation products of fluvalinate formed on the crop were identified and characterised as phenoxybenzoic acid and 2‐[2‐chloro‐4‐(trifluoromethyl)anilino]‐3‐methylbutanoic acid. They were estimated in day‐5 and day‐10 samples of chickpea crop as their methyl esters by gas liquid chromatography.     

Control of hydrogen sulphide in digestor gas using iron salts

Different dosages of ferrous chloride and ferric chloride were added to digestors separately, and the volumes of methane and hydrogen sulphide contained in the digestor gas (biogas) were monitored. It was noted that the effects of adding of 16, 18 and 32 kg ferrous chloride/ tonne volatile solids, and 16 and 18 kg ferric chloride/tonne volatile solids were similarly effective in controlling the hydrogen sulphide levels.

According to an average amount of undigested sludge (primary sludge mixed with surplus activated sludge) of 41 tonne volatile solids produced each day during the sewage treatment process in Shatin sewage treatment works, and the required dosage of 16 kg ferric chloride/ tonne volatile solids, the amount of iron salts required should be 656 kg/day or 3.3 mg/L for the actual application, based on an average sewage flow of 200,000 m³/day.     

On the association between the column ozone and the spectral solar ultraviolet radiation

An estimation of the increase in the daily spectral solar ultraviolet radiation reaching the ground is attempted, by using the daily total ozone observations made by the Total Ozone Mapping Spectrometer (TOMS) flown on the satellite Nimbus‐7 during 1978–1992. This investigation has been performed for the high latitudes by employing a recently proposed parametric model for the estimation of the spectral solar ultraviolet radiation at the earth's surface considering the total ozone content and various meteorological parameters.     

Heavy metal contents of the sperm whale physeter macrocephalus and the bottle‐nosed dolphin tursiops truncatus beached on Languedoc‐Roussillon seaside (Mediterranean,France)

The contamination of Sperm Whale Physeter macrocephalus and bottle‐nosed dolphin Tursiops truncatus by lead is less than detection limit, insignificant by cadmium and nickel, not very high by copper and quite high by zinc. On the other hand, the concentration of mercury, very low for Sperm Whale, is very high for bottle‐nosed dolphin.

The pollution of Physeter macrocephalus is significantly lower than that of dolphin Stenella coeruleoalba and probably that of other species of cetaceans living near the coast; this might be due to its pelagic life and its diet.

The mercury pollution of Tursiops truncatus (especially that of one of the two subjects analyzed) is quite similar to that of Stenella coeruleoalba. This might be due to the fact that Tursiops truncatus can live in the open sea just as well as close to the seashore.     

Induction of mercury‐binding peptide in whole cells and anucleated cells of Acetabularia calyculus

The present study reports the isolation and partial purification of a mercury‐binding polypeptide in whole and anucleated cells of Acetabularia calyculus. Sephadex G‐75 Gel filtration showed that cells exposed to Hg exhibit a major peak of protein(s) concomitant with both, a major peak of Hg (revealed by atomic absorption spectroscopy), and the major peak of mercury‐thiolate complex (based on a high 254 nm absorbance) accompanied by high content of SH groups. SDS‐Page electrophoresis showed that this peak contains one major polypeptide of apparent molecular weight 27.000 dalton. These results are in agreement with our previous finding of unusually high bioconcentration factor of Hg in Acetabularia related to the induction of a polypeptide in both, whole and anucleated cells of Acetabularia, in presence of Hg.     

焦化废水中有机物的识别、污染特性及其在废水处理过程中的降解

采用液-液萃取辅以硅胶、氧化铝净化的方法,并结合GC/MS分析技术,系统分析了焦化废水中有机物的组成.在焦化废水中检测到15类558种有机物.根据有机物的分子结构、废水中的含量、毒性及环境效应,筛选出焦化废水中的特征性有机污染物,以区别于其它工业废水,可作为追溯环境中污染物来源的依据.经物理、生物和化学处理后,焦化废水中大部分有机物被去除,其中,对去除率的主要贡献是生物处理阶段.为了更好地考察生物处理阶段对有机污染物的去除特征,选定酚类、多环芳烃和喹啉类物质作为研究对象,分析了3类特征性污染物在A/O2工艺各单元中的去除状况及组成变化特征.