• 한국산업보건학회지
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• 제6권1호
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• pp.97-108
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• 1996

A new type of passive samplers were designed and produced by authors. After evaluating the quality of activated carbon by measuring recovery rate of organic vapors and steadiness of sampling rate, activated carbon with 30 - 35 mesh produced by Company S in Korea was selected. In each passive sampler, an amount of 400 mg of the activated carbon was filled in 25-mm cassette and covered by fixed screen (or wire screen with 100 mesh). In addition to the fixed screen, a wind screen (or wire screen with 300 mesh) was also attached at outer face. The sampling rate of the new Korean passive samplers was estimated Conclusions obtained in the study are as follows. 1. Sampling rates of the newly developed Korean passive samplers were affected by sampling time. For n-hexane, sampling rates of 15- and 60-minute samples were 70.92 and 37.45 ml/min, respectively. Sampling rate of both 200- and 450-minute samples was 25.96 ml/min. It is concluded that, when passive samplers are used for measuring organic vapors, samples be collected longer than 60 minutes. 2. Sampling rate of the passive samplers was also affected by airborne concentration of organic vapors. Lower sampling rates were determined at level of 1/2 threshold limit values (TLVs) recommended by the American Conference of Governmental Industrial Hygienists (ACGIH). It is recommended that sampling rate of the passive samplers be obtained at site by measuring concentrations using both the NIOSH Method and passive samplers simultaneously. 3. When the passive samplers, which collected organic vapors, were exposed to clean air for five hours, there was no significant loss of organic vapors due to reverse diffusion. 4. When samples were stored at room temperature ($21.8{\pm}0.7^{\circ}C$) and refrigerator ($3.8{\pm}0.7^{\circ}C$), there was no significant difference in the accuracy of results. For trichloroethylene and n-hexane, accuracies were within 25 % at both temperatures until seven days. However, poor accuracy exceeding 25 % was indicated in toluene from the first day. It is recommended that samples be stored at freezing temperature below $0^{\circ}C$. 5. Sampling efficiency was significantly affected by direction of the passive samplers. Results of samplers facing wind and down, respectively, were compared. Lower amount of organic vapors were collected when the sampler was oriented down. It is recommended that, when air velocity is low in plants, the passive samplers be oriented to the wind. However, when air velocity is high, the passive samplers be oriented down.

• 대한환경공학회지
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• 제27권6호
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• pp.606-613
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• 2005

본 연구에서는 실내공기 중 포름알데히드를 측정하기 위해 세 가지 다른 반응의 흡광광도법(비색분석)을 응용한 뱃지형 확산측정기를 평가하였다. 흡수여지의 세척방법을 비교한 결과 사용된 세척용액의 종류에 관계없이 세척하지 않은 경우 보다 양호한 세척효과가 나타났다. 각 측정방법에서 사용될 흡수액의 농도는 시료채취율을 기준으로 정하였다. 평가된 공시험 값은 측정방법별로 15% 이내의 편차를 가진 것으로 나타나 대체적으로 안정적인 것으로 나타났다. 확산측정기의 재현성은 MBTH법이 상대표준편차 10% 이내로 가장 양호하며, 채취된 포름알데히드 양과 시간가중평균농도와의 상관관계는 세 가지 측정방법 모두 양호한 것으로 나타났다. 검출한계 및 정량한계는 시료채취율이 가장 좋은 MBTH법이 다른 측정방법과 비교하여 가장 낮게 나타나 시료채취율이 가장 크고 정량한계가 낮은 측정방법일수록 포름알데히드 측정에 요구되는 측정시간이 감소되는 것으로 나타났다.

• 환경생물
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• 제39권1호
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• pp.100-107
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• 2021

국내 고농도의 초미세먼지 발생 빈도 증가와 함께 그 전구물질인 NH₃와 관련한 연구가 활발히 진행 중이다. NH₃ 배출에 있어 농업의 기여율이 높은 것은 자명한 사실이다. 그러나 비료 사용이 농경지 대기 중 NH₃ 농도에 장기간 미치는 영향에 관련한 연구는 미비한 실정이다. 따라서 본 연구에서는 수동식 NH₃ 확산형 포집기를 활용해 11개월간 농경지 대기 중 NH₃ 농도를 관측하였다. 그 결과 비료 살포 직후 한 달 동안 NH₃ 배출의 영향이 가장 큰 것으로 나타났다. 그 이후 여름철 기온 상승으로 NH₃ 휘발이 촉진되어 대기 중 농도가 증가할 것으로 예상하였으나, 54일간의 지속적인 강우로 인하여 대기 중 높은 암모니아 농도는 관측되지 않았다. 그 후 NH₃ 농도는 가을과 겨울을 거치면서 점차 감소하였다. 비료의 영향력이 감쇠한 시점 이후에는 기온이 감소할수록, 그리고 강수량이 증가할수록 NH₃ 농도는 감소하는 것을 상관분석을 통해 확인할 수 있었다. 종합해 보면, 국내 NH₃ 배출량에서 비료의 기여율을 연구하는 데 있어 비료 살포 직후 최소 한 달 동안은 집중적으로 살펴보아야 할 것이며, 현장 연구 시 강수량과 무강우 일수 등의 기상 정보도 함께 고려해야 할 것이다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제24권6호
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• pp.16-25
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• 2019

Anthropogenic polycyclic aromatic hydrocarbons (PAHs) are formed by the incomplete combustion of fuels and industrial waste. PAHs can be widely exposed to the environment (water, soil and groundwater). PAHs are potentially toxic, mutagenic and/or carcinogenic. Fundamental studies such as biota uptake (e.g., earthworm and plant) of PAHs are highly needed. It is necessary to develop alternative ways to evaluate bioavailability of PAHs instead of using living organisms because it is time-consuming, difficult to apply in the field, and also exaction method is tedious and time-consuming. In this study, sorption behaviors of phenanthrene were evaluated to predict the fate of PAHs in soils. Moreover, bioaccumulation of PAHs in an artificially contaminated soil was evaluated using pea plant (Pisum sativum) as a bioindicator. A novel passive sampler, organic-diffusive gradient in thin-film (o-DGT) for PAHs was newly synthesized, tested as a biomimic surrogate and compared with plant accumulation. Sorption partitioning coefficient (K_P) and sorption capacity (K_F) were in the order of natural soil > loess corresponding to the increase in organic carbon content (f_oc). Biota-to-soil accumulation factor (BSAF) and DGT-to-soil accumulation factor (DSAF) were evaluated. o-DGT uptake was linearly correlated with pea plant uptake of phenanthrene in contaminated soil (R²=0.863). The Tenax TA based o-DGT as a biomimic surrogate can be used for the prediction of pea plant uptake of phenanthrene in contaminated soil.