Concentrations and analytical methods for formaldehyde, acetaldehyde, and acrolein in air are reviewed.Much attention is paid on formaldehyde because of its high level concentration and of its toxicity.Reliable analytical methods are chromotropic acid method, pararosaniline method, AHMT method, and DNPH/HPLC methods.Among several continuous methods for formaldehyde analysis in air, AHMT method is very promissing.DNPH/HPLC method seems to be very useful for acetaldehyde analysis and 4-hexyl-resorcin method and oxazolidine derivatization/GC method for acrolein analysis at the present time.

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Dioxin and related compounds including polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and non-ortho coplanar PCBs have been focused recently in the environmental pollution due to their extremely high toxicity.
In this paper, dietary intake, exposure to food and human body, and pharmacokinetics of these compounds were reviewed. In addition, a risk assessment on dietary intake and a comparison between these compounds and PCBs on excretion from body were discussed.

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Destruction and formation of chlorinated hydrocarbons in combustion of waste materials including organochlorine solvent, chlorine-containing polymers, etc. were investigated. Results and conclusions were as follows : (1) Most of volatile chlorinated hydrocarbons evolved from waste incinerators were emitted from stack ; (2) destruction efficiency of chlorinated hydrocarbons by combustion depends on media containing chlorinated hydrocarbons ; and (3) main sources of volatile toxic compounds such as chlorinated hydrocarbons were waste plastics.

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A gas chromatographic method using air as the carrier gas for hydrocarbons, alcohols and volatile fatty acids was investigated. The moisture in the air was excluded by dryer at 5°C, organic compounds were decomposed on copper oxide at 400°C, and the refined air used as the carrier gas for gas chromatography. N, N-Diphenyl-p-phenylenediamine was added to the liquid phases of several column packing materials as an antioxidant, and the packing surfaces were treated with dicumyl peroxide for cross-linking in air at 250°C. The air carrier gas was much the same as nitrogen gas with respect to HELP curves for benzene and n-hexane. Separation and reproducibility of hydrocarbons, alcoholes and volatile fatty acides were not found different between using a carrier gas of air or nitrogen. This method was applied to determination of benzene in the atmosphere. The column showed no deterioration after more than 100 days at 120°C with air as the carrier gas.

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A novel TCDD (2, 3, 7, 8-tetrachlorodibenzo-p-dioxin) cancer potency factors (CPFs) estimates on the basis of current biologial knowledges were derived using PB-PK (physiologicallybased pharmaco-kinetics) and MKV (Moolgavkar-Knudson-Venzon) two-stage model of carcinogenesis. Risk-specific-doses (RsD) estimates at a 1×10^-6 risk level were 4.8-24 pg/kg/day and the corresponding CPFs were 210-42 (mg/kg/day) ^-1.
Ambient air concentrations of dioxins emitted by MWI were predicted at the ground level using actual stack measurement data. Estimation of upper most cancer risk which associated with exposure through inhalation does not exceed 10^-8 in the vicinity of the incinerator.
As an alternative to individual cancer risk, population exposure value which was defined as the product of individual dose and number of individuals affected, appeared to be well suited as guideline for a decision making such as the selection of incinerator sites.

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Recently, Pesticides were spread into paddy fields using helicopters. However, improper spray of pesticides sometimes may cause serious water quality problems. In this paper, we report about the runoff of insecticides (CVMP and malathion) spread by helicopters from paddy fields.
The effluent from paddy fields run into four downstream of rivers, Shin-River, Nishi-River, Hirodori-River and Old-Hirodori-River. The concentration of insecticides in the river water reached to 69.2 μg/1 (CVMP) and 7.50μg/1 (malathion) . Moreover, the concentration of CVMP in the water for irrigation reached to 277μg/1.
The insecticides in the river water were disappeared within 2 days after the spray.
The effluent ratio of CVMP into the rivers was 5.2% (1st examination) or 4.6% (2nd examination) .

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In generally, commercial PCB preparations have been reported to contain toxic polychlorinated dibenzofurans (PCDFs) . It is also known PCDFs are formed by heating of PCB. Sometimes, the fluorescent light condensers are exploded by over-heating, and a PCB preparation (KC-300) as an insulator in the condensers was sprinkled around rooms.
In this paper, toxic PCDFs and PCDDs in the insulator of fluorescent light condensers were examined using capillary GC / high resolution MS (HRMS) . The concentration of PCDFs in the insulators was 1948 ppb, while that in unused KC-300 was 3385 ppb. No change in the values between in the exploded and unexploded insulators was observed, PCDFs in insulators and KC-300 were respectively composed of tetra- (TCDFs) through hexachlorinated dibenzofurans (HxCDFs) and TCDFs through heptachlorinated ones (HpCDFs) . TCDFs was the main component in all samples. However, the contents of TCDFs plus pentachlorinated dibenzofurans (PeCDFs) in total PCDFs of the exploded and unexploded insulators were different from that of KC-300. Namely, while the content of TCDFs plus PeCDFs in total PCDFs of KC-300 was 83.7%, those in exploded and unexploded insulators were 96.4% and 97.2%, respectively.
On the other hand, 2, 3, 7, 8-TCDD toxicity equivalent (TEQ) levels of PCDFs were calculated by international toxicity equivalent factor (I-TEF) . The total TEQ levels of PCDFs in KC-300, the insulators of exploded and unexploded condensers were 88.4 ppb, 50.0 ppb and 45.1 ppb, respectively.
No PCDFs were detected in KC-300 and the insulators of fluorescent light condensers.

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Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzof urans (PCDFs), polychlorinated biphenyls (PCBs), chlordanes and DDE were measured in both the vapor and particle-bound phases.
The concentration of total 2, 3, 7, 8-TCDD equivalents in air, using International toxic equivalents factors (I-TEF), was 0.22pg/m³ (0.04 pgTEQ/m³ from PCDDs, 0.18pgTEQ/m³ from PCDFs) . Daily intake of PCDD/PCDF via air was estimated to 3.3pgTEQ/day.

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In this paper, thé author has presented the Temperature Programed Retention Indices (PTRI) of 1, 340 environmental chemicals on methyl silicone capillary column. PTRI is defined as follows:
PTRI =100×Z +100× (T_X-T_Z) / (T_z+1-T_Z)
Z: Carbon number of n-alkane eluted just before the target compound.
T_X, T_Z and T_Z+1: Retention times of the target compound (x), n-alkane of z and z+1 carbon munber, respectively.
The author expects these data are applied to identifications of environmental chemicals using GC/MS.

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