Immune function is susceptible to nutritional and environmental status of heavy metals. The common immunological manifestations and related health effects are described resulting from deficiencies of essential heavy metals and excess exposure to essential or toxic heavy metals. T cell dysfunction in zinc deficiency exemplifies immunosuppression in deficiencies of essential metals. It may be due to impairment of zinc-dependent metabolism in immune cells and/or decreased activity of thymulin, a zinc-dependent thymic hormone. The exposure to cadmium as well as mercury can stimulate immune cells to induce autoantibody formation, which requires the presence of T cells and seems to be associated with development of glomerulonephritis. Thus T cells may interact more selectively with zinc, cadmium and presumably other heavy metals. Immunological disturbance associated with heavy metals can be a model for studying potential risks of chronic diseases originated from nutritional and environmental status.

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To evaluate the toxicities of 37 xenobiotics detected in drinking water ; primary cultures of rat hepatocytes were treated with the xenobiotics at a concentration of 0.5 mM. The toxicities were assessed by four cellular markers : leakage of intracellular lactate dehydrogenase (LDH) activity, glycogenolytic activity as a specific function of hepatocytes, intracellular glutathione content, and observations of cytopathic effects. The cytotoxic assay revealed that pesticides of xenobiotics used in the current study were the most toxic at μM levels, that phenolic compounds had potent toxicity for the cultured cells while benzoic compounds did not, and that 3-carbon compounds with substitution of hydrogen to bromine or chlorine at both positions 1 and 3 were highly toxic. The order of hepatotoxicity on the basis of IC₅₀ was, 1, 3-dichloro-2-propanone > pentachlorophenol ⩾ 1, 2-dibromo-3-chloro-propane > heptachlor > 2, 4, 6-trichlorophenol ⩾ 2, 4, 6-tribromophenol. Since lag times were observed for the expression of cytotoxicity by the pesticides, biotransformation appeared important for the toxicity. Currently the concentration of pesticides is very low in the environment, and therefore the possibility of causing an impact on human health is low. However, the long lifetime and high lipophilicity of pesticides give them the potential to become some of the greatest environmental toxicants.

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Several kinds of absorbents, which were used for the determination of chlorine in the air by the pyridine·pyrazolone method, were investigated. Among p-toluenesulfonamide, sulfamic acid, 5, 5-dimethylhydantoin, isocyanuric acid and succinimide, only p-toluenesulfonamide was useful for the absorbent ; the others were useless because of a consumption of chlorine, a slow formation velocity of cyanogen chloride or an instability of chlorine. Furthermore, most of commercial potassium cyanides, which were also used for the determination method, were found to contain a reducing impurity. The impurity was a sulfite ion, and its content ranged from 100μg to 1400μg per 1 g of each potassium cyanide tested.

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A thermospray high-performance liquid chromatographic-mass spectrometric (LC-MS) method has been developed for the analysis of sulfonamides such as sulfachlorpyridazine, sulfadiazine, sulfadimethoxine, sulfadimidine, sulfadoxine, sulfamerazine, sulfamethoxazole, sulfamethoxypyridazine, sulfamonomethoxine, sulfaquinoxaline, sulfathiazole and sulfisomidine. The LC separation was carried out on a TSK-gel ODS-80T_M by using 0.05 M ammonium acetate (pH 4.5)- acetonitrile (7 : 3) as the mobile phase, at a flow rate of 0.8 ml/min. The vaporizer temperature was set to 155°C and ion source block temperature to 280°C. The mass spectra obtained from sulfonamides were very simple, with base peaks corresponding to protonated molecular ions MH⁺. The calibration curve for sulfadimidine was rectilinear from 0.2 to 20 ng with the detection limit by selected ion monitoring (SIM) was about 100 pg. Similar results were obtained with other sulfonamides. An excellent correlation between the results of the thermospray LC-MS method and HPLC method was obtained (γ=0.981).

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LAS resistance and degradability were examined on 354 heterotrophic bacteria, isolated on PYG agar medium from a total of 18 river waters. All of the isolates tested could grow on the agar medium containing LAS at 3 mg/l, whereas 185 strains (52.2%) and 31 strains (8.7%) were tolerant to 30 mg/l and 300 mg/l of LAS, respectively. The predominant type among the most tolerant bacteria was Enterobacteriaceae (35.5%), that was reconfirmed by the classification of the highly resistant isolates from the other river water sample. LAS degrading ability was detected only in five of the 354 strains, all of which belong to Pseudomonas sp. but not to Enterobacteriaceae, and were sensitive to 300 mg/l of LAS, showing that the highly tolerant bacteria were not always LAS degrading bacteria.

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A new sampling method by using both a quartz fiber filter (QF) and an activated carbon fiber filter (AF) as a back up filter was developed for gas chromatographic analysis of airborne pesticides, i.e. fenitrothion (MEP), malathion, tetrachlorvinphos (CVMP) and fenobucarb (BPMC). Air was passed at 10 l/min through both a 17.3 cm² QF and an AF. The both filters sampled were put together and extracted ultrasonically with 3 ml of benzene-ethanol (4 : 1, v/v) for 10 min followed by centrifugation at 2000 rpm for 10 min. The supernatants were analyzed with GC/FPD or GC/FTD. Extraction efficiencies of 5 μg of each pesticide from a QF and an AF were 89.3-107%. Sampling efficiencies of 4 gaseous pesticides with an AF were about 100%. Overall recoveries of 5μg of each pesticide were 90.8-97.6%. Detection limits of MEP, malathion, CVMP and BPMC were 0.6, 1.2, 5.2 and 1.0 ng/m³ respectively for 3.6 m³ of air.

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Quantitative structure-activity relationship was studied on antimutagenic phenol carboxylic acids. Antimutagenic activities of 117 compounds were examined with Ames test by using Salmonella typhimurium TA98 with S9 mix. Benzo[a]pyrene was used as a reference mutagenic substance. Seven compounds which were hardly soluble in the test medium and six compounds which showed a killing effect were omitted in the evaluation of antimutagenicity. Theory of quantification I was applied to this study. The chemical structures of the above 104 compounds were classified into 3 items : principal structure, substituent groups, and the functional groups of side chain. The results between the range of standardized categorical weight and partial coefficient did not coincide. As the categorical weight of phenols was so great, that 10 phenols compounds were omitted, and then recalculated. It was found that φR (1) OH (3, 4, 5), coumarin, φR (1) OCH₃ (3, 4, 5), and φR (1) OH (2, 4, 6) acted for enhancing antimutagenicity, while φR (1) CHO (4), φR (1) COOH (2), and φR (1) COOH (4) acted for enhancing mutagenicity. The regression line of structure-antimutagenic activity lied in Y=0.62X+9.15. (The following symbols are used : X, Y ; observed and calculated values of antimutagenic activity, respectively, φ ; benzene ring, R ; side chain, and the numbers in parentheses ; the numbers of position for substituent groups)

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The inhibitory activity of hyaluronidase was found in the water extract of Gymnema sylvestre. The two active compounds were purified with gel filtration, followed by anion exchange chromatography, and their structural study were performed by GC-MS and carbazole method. On the bases of these results, the two active substances were proved to be pectic substances containing 73% D-galacturonic acid with approximately 4.0×10⁴ and 2.0×10⁴ of molecular weight as I and II, respectively.

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Perilla ketone (PK), a potent lung toxin, in Perilla Herb was determined by capillary gas chromatography/mass spectrometory (capillary GC-MS). Without any cleanup, PK in ethyl acetate extract from a Perilla Herb sample was well separated by using a middle polar fused silica column (DB-17), and for the identification, mass chromatography monitoring m/z 166 from the molecular ion and m/z 110 and 95 from the fragment ions was carried out under an E.I. condition. Selective ion monitoring (SIM) of the both McLafferty rearrangement peaks, m/z 110 from PK and 112 from menthone added as an internal standard, allows sensitive and accurate quantification. The calibration curve was rectilinear in the range from 0.005 ng to 10 ng with the identification limit of 0.001 ng. The average recovery was 97.6% for PK added to Perilla Herb at the level of 300μg/500 mg. By this method, crude drugs on the market were analyzed : PK detected from 9 out of 25 samples (36%), and the amounts of PK ranged from 1.1 to 119.9 mg/100 g. It turned out that the PK doses taken in a day are less than 1/10⁴-1/10³ levels of LD₅₀ to the mice.

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A method for the determination of hexabromocyclododecane (HBCD), a flame retardant, in polyester fabrics was developed. HBCD was extracted from polyester fabrics with dichloromethane. The extract was cleaned up by silica gel column chromatography with dichloromethane as an eluent. The eluate was evaporated to dryness. The residue was dissolved in acetonitrile and injected to a high performance liquid chromatograph. The analytical conditions were as follows : column, Capcell pak C18 (Shiseido, 150 mm×4.6 mm i.d.) ; mobile phase, acetonitrile-water (85 : 15) ; flow rate, 1.0 ml/min ; detection wavelength, 254 nm. The calibration curve for HBCD was linear in the range of 1-50 μg. The minimun detectable concentration of HBCD was 0.5 mg/g. The contents in commercially available polyester curtaines were 5.3-35.6 mg/g.

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A simultaneous determination method for five organic acids in vinegar has been established by photometric ion chromatography. Both trace components (lactic, gluconic, succinic and pyroglutamic acids) and the major component (acetic acid) in vinegar were separated on a TSK gel IC-Anion-PW column with 0.45 mM o-aminobenzenesulfonic acid aqueous solution as an eluent. Their elutions were detected as positive peaks before the system peak, and a negative peak after that by a UV monitor. The sensitivities of trace components were enhanced by adjusting their elutions close to the system peak. The lowest detection limits were 10μM lactic acid, 5μM gluconic and succinic acids and 3μM pyroglutamic acid, respectively. The only pretreatment necessary was dilution of vinegar 100-fold with the eluent. The results obtained by the proposed method were in good agreement with those by the enzymatic one.

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A simple determination for eight kinds of organophosphorus pesticides (OPs) from animal tissues was newly developed. OP was extracted from the sample with acetonitrile, added 2% NaCl solution, and reextracted with n-hexane. The organic layer was loaded to a Sep-Pak silica cartridge and OP retained in the cartridge was eluted with ethyl acetate. The eluate was dried up under a stream of nitrogen. The residue was dissolved in n-hexane and the OP was determined by use of gas chromatograph (GC) equipped with a flame photometric detector (FPD). When nine OPs were separately added to four tissues (muscle, liver, adipose tissue and blood) of hen at the level of 5μg per 0.5 g of tissue weight, recoveries of fenitrothion, malathion, fenthion, parathion, cyanofenphos, EPN and leptophos ranged from 79.8% to 96.9%. In the case of cyanophos, recoveries from muscle, liver and adipose tissue were from 83.1% to 91.9%, but recovery from blood was 60.1%. Recoveries of dichlorvos from muscle, liver, adipose tissue and blood were below 18.8%. These results demonstrate that this simplified method is applicable to the determination of the above eight OPs except dichlorvos from animal tissues.

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The enzymatic analysis of cyanogenic glycosides by using a Conway's microdiffusional apparatus was applied to some processed foodstuffs. For their application to the foodstuffs containing organic acids or ethanol, effects of pH and ethanol content on hydrolysis with β-glucosidases such as linamarase and almond emulsin were investigated. The optimum pH of the hydrolysis was between 5-6, and the hydrolysis was not carried out completely below 3.5. In addition, the ethanol content below 10% gave no influence on the hydrolysis. The preparation for a test solution was modified as follows ; 30 ml of 0.01 N NaOH solution was added to 10 g of sample, and after homogenizing the mixture, adjusting the pH to 5-6, the mixture was made up to 100 ml with sodium citrate buffer (pH 5.2). By the proposed preparation method, the recoveries of linamarin and amygdalin added to bean paste, pickled ume (Prunus nume SIEB. et Zucc), ume liquor at levels of 1-400μg/g of cyanide were in the range of 89-99% and the detection limit was 1μg/g of sample. This method was applied to 11 kinds of commercial foods, and total cyanide detected in the range of 1-598μg/g. It is concluded that this modified method was widely applicable for the analysis of cyanogenic glycosides in foods.

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Twenty nine kinds of organophosphorus pesticides were simultaneously measured by FPD-GC with two kinds of capillary columns (DB-210 and CBP-10). Reproducibility for peaks area of the pesticides in chromatograms were the range of 4.6-21.6%. Determination method of the 29 pesticides in foods was systematically established as follows. A) Pesticides in vegetables and fruits were extracted with acetone, re-extracted with 20% CH₂Cl₂-hexane and determined by GC. Recoveries of the pesticides in cucumber, potato, Japanese persimmon, cabbage, apple and mandarin orange were the range of 53.2-102.2%. B) Pesticides in garlic, onion, scallion were extracted, re-extracted by the same method with A, then purified by silica-gel column chromatography. Recoveries of the pesticides were the range of 31.2-89.9%. C) Pesticides in rice, wheat, soy bean and corn were extracted, re-extracted by the same method with A, then partitioned with hexane-acetonitrile and purified by silica-gel column chromatography. Recoveries of the pesticides were the range of 36.7-95.8%.

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