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1.
An enhanced dual coil 2,4-dinitrophenylhydrazine (DNPH) derivatization method (dual coil/DNPH) allowed the quantitative determination
of formaldehyde (HCHO) in ambient air. In this method, traceable HCHO was collected using a coil sampler connected in series
and lacking a long sampling tube. It was then analyzed using liquid chromatography followed by UV detection of the DNPH derivatives.
The method is based on the reaction of formaldehyde with DNPH to produce 2,4-dinitrophenylhydrazone. The detection limits
(3σ) were 0.10–0.40 ppbv with a precision ranging from 0.84 to 4.09% RSD. The results of dual coil/DNPH and conventional DNPH
cartridge methods were generally well correlated: HCHO (dual coil/DNPH) = 0.97 (±0.13) vs. HCHO (DNPH Cartridge) + 0.33 (±0.33),
r = 0.82. The dual coil/DNPH method was used to measure gaseous HCHO in the atmosphere of Metropolitan Seoul during the summer
2000 and 2001, and in Gwangju during the fall of 2001 and 2002. The daytime mean concentration of HCHO was 4.52 (±5.69) and
3.21 (±1.27) ppbv in Metropolitan Seoul for 10–12 August 2000 and 29–31 May 2001, respectively, and 1.73 (±0.98), 3.04 (±2.25),
2.70 (±1.70), and 2.01 (±2.28) ppbv in Gwangju City during 22–27 September 2001, 17–24 October 2001, 9–13 October 2002, and
28 October to 2 November 2002, respectively. The HCHO in Seoul from 10–12 August 2000 was mainly the result of photochemical
processes, while direct emissions from vehicles and long-range transport of air from China contributed during 29–31 May 2001.
During 22–27 September 2001, 17–24 October 2001, and 9–13 October 2002 in Gwangju, the HCHO came primarily from photochemical
processes, although some air affected by biomass burning admixed in the late afternoon. The increase in the HCHO concentration
on 20 October 2001 and from 28 October to 2 November 2002 was attributed mainly to direct emissions from biomass burning in
farmland near the measurement site. 相似文献
2.
Water quality assessment: surface water sources used for drinking and irrigation in Zaria,Nigeria are a public health hazard 总被引:1,自引:0,他引:1
Chigor VN Umoh VJ Okuofu CA Ameh JB Igbinosa EO Okoh AI 《Environmental monitoring and assessment》2012,184(5):3389-3400
We assessed the quality and pollution status of source surface waters in Zaria, Nigeria by monitoring the nature, cause and
extent of pollution in Samaru stream, Kubanni River and Kubanni dam over a period of 10 months, between March and December
2002. A total of 228 water samples was collected from 12 sites and analysed for a total of ten physicochemical and one bacteriological
quality indicators, using standard methods. Aesthetic water quality impairment parameters were also observed. The mean values
of most water quality parameters were significantly higher (P < 0.05) in both the stream and river than in the dam. There was no significant correlation between faecal coliform counts
(FCC) and water temperature (in the range 15–33°C); pH (5.77–7.32); and turbidity (1.4–567 NTU). The high FCC ranged from
2.0 × 101 to 1.6 × 106 MPN/100 ml and exceeded the WHO standards for drinking water and water used for fresh-produce irrigation, and correlated
positively (P < 0.05) with conductivity (in the range 68–1,029 μS/cm); TDS (10.0–70.0 mg/l); TSS (10.0–70.0 mg/l); Cl (7.5–181 mg/l); PO4−P (0.01–0.41 mg/l); NO3−N (0.6–3.8 mg/l) and BOD5 (0.1–14.9 mg/l). The main pollution sources were municipal wastewater, stormwater runoffs, the ABU sewage treatment plant,
abattoir effluents and irrigation farms treated with chemical fertilisers. We conclude that these water bodies are potentially
hazardous to public health and that proper sewage treatment and river quality monitoring are needed to warn against hazards
to public health. 相似文献
3.
This study aimed to optimise the methodology for the use of Corophium insidiosum in a bioassay. Taking into account that it would be suitable to execute the bioassay with organisms having a good sensitivity
during the year and low mortality in control sediment, the influence of different temperatures (10–15–20 and 25°C) has been
examined. C. insidiosum was collected during August, November 2005 and January 2006, in Mar Piccolo basin (Ionian sea). The results obtained show
that this species mortality in the negative control sediment, ranged from 2.6 ± 0.6% at 10°C in August to 17 ± 2.2% at 20°C
in November, at different temperatures tested. At 20°C there were significant differences in mortality among different months
examined. Indeed no relationship among months was found at 15°C. Significant differences between August and November at 25°C,
between November and January were not found at 10°C. The 96-h LC50 values found for cadmium at all temperature experimental
conditions ranged from 2.11 mg/l (1.57–2.82) to 0.70 mg/l (0.54–0.93). The highest values were found at 10°C in November and
January. The results showed that the optimal temperature for the bioassay seems to be between 15°C and 20°C. Even if, at 20°C
the mortality differs significantly among organisms sampled. 相似文献
4.
A serious forest decline of Betula ermanii Cham. has been observed at Mt. Mae-Shirane, Oku-Nikko, Japan, where high ozone (O3) concentration and severe water deficiency have been measured. In order to consider the possibility whether O3 and/or water stresses could have been the causes of the forest decline of B. ermanii, plant growth experiments were conducted in environment-controlled growth cabinets. Two-year-old seedlings of B. ermanii were exposed to either charcoal-filtered air (O3 concentration <5 ppb) or 50 ppb O3 (daily average, ranging between 20–100 ppb) for 123 days at 20.0/12.5 ± 1.0°C (day/night) and 70/80 ± 7% relative humidity
(day/night). Simultaneously, seedlings were treated with three watering regime: 1.0 < pF < 1.8 (no water stress), 1.8 < pF < 2.5
(mild water stress) or 2.5 < pF < 3.0 (severe water stress). O3 exposure significantly reduced the dry weights of leaf, root and the whole plant, while water stress significantly reduced
the dry weights of each organ and the whole plant. Significant reductions of net photosynthesis, transpiration and stomatal
conductance were also observed under O3 and/or water deficiency treatments, while contents of RuBP carboxylase/oxygenase (Rubisco), chlorophyll
a+b
and some essential nutrient elements (N, P, K, Mg and Ca) were not markedly changed. It was suggested that the decrease in
net photosynthetic rate induced mainly by stomatal closure was the major cause of the growth reduction under O3 and/or water stresses. No significant interactions between O3 and water stresses were observed in terms of the depression of dry matter production, which suggested that simultaneous stress
treatments of O3 exposure and water deficiency could affect the tree growth of B. ermanii additively. 相似文献
5.
Chemistry of groundwater in Gulbarga district, Karnataka, India 总被引:1,自引:0,他引:1
Majagi S Vijaykumar K Rajshekhar M Vasanthkumar B 《Environmental monitoring and assessment》2008,136(1-3):347-354
Groundwater quality of Gulbarga District is extensively monitored for two years of study period from October 1999 to September
2001. Twenty-five different sampling stations were selected for the study purpose in the city and five selected villages in
the district. Gulbarga districts lies in the northern plains of Karnataka State, covers an area of 16,244 km2 and lies between 16°-11′ and 17°-19′N latitude and 76°-54′E longitude The study revealed that the water sources in the area
are heavily polluted. The major water quality parameters exceeding the permissible limits during all the seasons are total
hardness, calcium hardness, magnesium hardness, alkalinity and MPN (Bacterial count) and other parameters have shown distinctive
variation in different stations and season. Most of these parameters are correlated with one another. Statistical analysis
of the data is presented. 相似文献
6.
Atmospheric surface aerosol radiative forcing (SARF) ΔF, forcing efficiency ΔFe and fractional forcing efficiency ΔFFe evaluated from cloud-screened narrowband spectral and thermal-offset-corrected radiometric observations during the Asia dust
outbreak episodes in Gwangju, Republic of Korea are reported in this study. Columnar aerosol optical properties (aerosol optical
depth (AOD), τ
aλ, Angstrom exponent α, mass concentration of fine and coarse mode particles) were also reported for the station between January
2000 and May 2001 consisting of 211cloud-free days. Results indicate that majority of the AOD were within the range 0.25–0.45
while some high aerosol events in which AODs ≥ 0.6 were observed during the severe dust episodes. For example, AOD increases
from annual average value of 0.34 ± 0.13 at 501 nm to values >0.60 during the major dust events of March 27–30 and April 7–9,
2000, respectively. The α
501–870 nm which is often used as a qualitative indicator of aerosol particle size had values ranging from 0.01 to 1.77. The diurnal
forcing efficiency ΔDFe at Gwangju was estimated to be −81.10 ± 5.14 W m −2/τ
501 nm and −47.09 ± 2.20 W m −2/τ
501 nm for the total solar broadband and visible band pass, respectively while the fractional diurnal forcing efficiency ΔFDFe were −15.8 ± 0.64%/τ
501 nm and −22.87 ± 1.13%/τ
501 nm for the same band passes. Analyses of the 5-day air-mass back trajectories were further developed for Gwangju in order to
classify the air-mass and types of aerosol reaching the site during the Asia dust episodes. 相似文献
7.
Vertical ozone distributions observed using tethered ozonesondes in a coastal industrial city, Kaohsiung, in southern Taiwan 总被引:1,自引:0,他引:1
This work presents the vertical distributions of ozone and meteorological parameters observed with tethered ozonesondes and
meteorological radiosondes in the lower atmosphere during an ozone episode on March 25–27, 2003, in Kaohsiung City in southern
Taiwan. Kaohsiung is a coastal industrial city with inland mountain ranges to the east. Extremely complicated ozone structures
were identified that spanned day and night during the experimental period. During afternoons, the lower atmosphere was divided
into two stratified air layers with substantially different ozone concentrations. On the episode day (March 26), average ozone
concentration in the near-ground layer was 85 ppb and the aloft layer was 140 ppb. A very high ozone peak of 199 ppb measured
aloft likely resulted from an elevated large point source. Several no-ozone air layers, distributed throughout 400–750 m,
were observed to transport onshore during the nigh. As well, elevated ozone layers peaking at 60–90 ppb and 90–160 ppb were
detected below and above the no-ozone air layers, respectively. These complicated ozone structures were likely formed through
titration of plumes from large point sources and the circulations of sea breezes or combined sea-breeze/mountain flows in
the study area. 相似文献
8.
This study presents concentration levels of pollutants (lead, and cadmium) in tissues (livers, kidneys, muscles, and bones)
of shorebirds (Kentish Plovers (n = 5), Mongolian Plovers (n = 2), Dunlins (n = 6), Great Knots (n = 10), Terek Sandpipers (n = 10)) from Yeongjong Island, Korea in the East Asian–Australian migration flyways during the autumn migration in 1994–1995.
Lead concentrations in livers, in kidneys, in muscles, and in bones were significantly different among shorebird species.
Lead concentrations in livers of Kentish Plovers (4.76 ± 2.72 μg/wet g), Mongolian Plovers (2.05 μg/wet g), Dunlins (3.77 ± 1.07 μg/wet
g), and Great Knots (4.27 ± 3.19 μg/wet g) were less than the toxic level, and lead concentrations in livers of Terek Sandpipers
(1.20 ± 0.94 μg/wet g) were at the background level. Cadmium concentrations in livers, in kidneys, in muscles, and in bones
did not vary among shorebirds, and concentrations of cadmium in livers and in kidneys were at background level (respectively,
approximate 1 μg/wet g, approximate 2.67 μg/wet g) in all shorebird species. We suggest that interspecific differences of
lead and cadmium concentrations were attributed to differences in exposure time and differences of diet, microhabitats in
wintering ground. In livers and kidney of shorebirds from Yeongjong Island, lead and cadmium concentrations were higher than
other locations previously reported. 相似文献
9.
This is the first study related to the effects of cadmium (Cd) on the development and hatching of eggs of Loligo vulgaris. The eggs were exposed to concentrations varying from 10 to 100,000 μg Cd/l for up to 1 month. During the study period natural
sea water salinity (37 PSU), ambient temperature (ranging 16.5–21.5°C) and light conditions of 12-h light: 12-h dark for 744-h
were used prior to the hatching. For 96-h, mortality rate of 100% of the eggs was found at cadmium concentration of 100,000 μg
Cd/l, and the same mortality rate of the eggs were found at 1,000 and 10,000 μg Cd/l for 744-h and 696-h, respectively. Hatching
took place between hours 456 and 576 in the control group and between hours 480 and 576 in 10 and 100 μg Cd/l groups. Total
hatching rates were calculated to be 98.2 ± 1.6% for control group, 99.4 ± 0.6% for 10 μg Cd/l group and 98.6 ± 1.2% for 100 μg
Cd/l group. Hatching successes were estimated as 69.5 ± 13.8% for control group, 84.5 ± 8.2% for 10 μg Cd/l group and 76.9 ± 5.9%
for 100 μg Cd/l group. In the 100,000 μg Cd/l treatment, the egg degeneration began from animal pole of the eggs in 16 h,
and 50% and 100% of them died in the initial stage at 72-h and 96-h, respectively. In the 10,000 μg Cd/l group, the eggs which
reached at stage 19 (IX) were deformed and 50% and 100% of them died at 312-h and 696-h, respectively. In 1,000 μg Cd/l group,
however, the eggs developed abnormally from stage 21 (X–XI) and reached at stage 29 (XIX), and 50% and 100% of them died in
624-h and in 744-h, respectively. There were significant differences in survival rates of the eggs among the concentrations
(p < 0.05). The current study demonstrated that Cd adversely affects the development, survival and hatching of L. vulgaris eggs; however, no mortality was observed in 10 μg Cd/l and 100 μg Cd/l groups. 相似文献
10.
Licata P Naccari F Dugo G Fotia V Lo Turco V Potorti AG Di Bella G 《Environmental monitoring and assessment》2012,184(5):2881-2892
In the present study, we investigated the concentrations and distribution of organochlorine pesticides (OCs) and polychlorinated
biphenyls (PCBs) in intestine, liver, and muscle samples of 11 common buzzards (Buteo buteo) from Sicily used as bioindicator for monitoring pollution in environment. All samples of common buzzards were collected
at the “Recovery Center of Wild Fauna” of Palermo, through the Zooprophilactic Institute. Quantitative determination of OCs
and PCBs in the samples examined has been carried out using HRGC-ECD and GC-MS. The results obtained show the presence of
concentrations of ∑DDT and ∑PCB in almost all samples. Regarding ∑DDT (4,4′-DDE, 2,4′-DDD, 4,4′-DDD, 2,4′-DDT, and 4,4′-DDT), the highest concentrations were found in intestine (0.411 ± 0.050 μg/g) followed by muscle (0.130 ± 0.017 μg/g) and
liver samples (0.109 ± 0.014 μg/g). As regards the ∑PCB congeners (PCB-28, PCB-52, PCB-95, PCB-99, PCB-101, PCB-110, PCB-138,
PCB-146, PCB-149, PCB-151, PCB-153, PCB-170, PCB-177, PCB-180, PCB-183, and PCB-187), the highest concentrations were found
in intestine (1.686 ± 0.144 μg/g) followed by liver (1.064 ± 0.162 μg/g) and muscle samples (0.797 ± 0.078 μg/g). Our data
deserve particular attention not only for their significance but especially because they were recorded in Sicily, a region
with a very low risk of environmental pollution due to the shortage of industries. 相似文献
11.
Ozone dynamics in our study area (Castellon, Spain) is both strongly bound to the mesoscale circulations that develop under
the effect of high insolation (especially in summer) and conditioned by the morphological characteristics of the Western Mediterranean
Basin. In this work we present a preliminary analysis of ozone time series on five locations in Castellon for the period 1997–2003.
We study their temporal and spatial variations at different scales: daily, weekly, seasonally and interannually. Because both
the O3 concentration and its temporal variation depend on the topographic location of the observing station, they can show large
differences within tens of kilometer. We also contrast the variation in the ozone concentration with the variations found
for meteorological variables such as radiation, temperature, relative humidity and recirculation of the air mass. The link
between elevated ozone concentrations and high values of the recirculation factor (r=0.7–0.9) shown the importance of recirculating flows on the local air pollution episodes. 相似文献
12.
Yannopoulos PC 《Environmental monitoring and assessment》2007,135(1-3):163-180
An economic and quick methodology for performing a preliminary spatial assessment of a city air quality with the purpose to
identify locations and zones susceptible to high pollution levels is proposed. A Patras case-study is selected, regarding
the air pollutants of sulfur dioxide (SO2) and oxides of nitrogen (NOx). A total number of 451 samples of short duration, of which 225 were randomly picked in morning rush hours and 226 within
evening rush hours, were collected from 50 locations of the major Patras area during a year period, when peaks of primary
air pollutants usually occur. Concentration measurements at prescribed locations used to statistically calculate spatial average
concentrations approximating 1-h mean values with mean probable errors less than 25.9% for SO2, NO and NOx and less than 15.5% for NO2. Then iso-concentration contour diagrams plotted indicate high pollution zones and possibly appropriate locations for continuous
or random monitoring according to the European Community (EC) Directives. The 1-h mean concentrations were in good correlation
to the corresponding traffic rates and useful relationships are given (0.54 ≤ r ≤ 0.63). In addition, comparisons with data available for other cities, as well as with the limit and guide values provided
by the EC and the World Health Organization (WHO) were given. The present data could be useful for the design and optimization
of a city network of stations for monitoring air quality, for environmental impact assessments, future reference and comparisons
due to city development needs, as well as for validating dispersion models. 相似文献
13.
Vasanthavigar M Srinivasamoorthy K Prasanna MV 《Environmental monitoring and assessment》2012,184(1):405-420
The Thirumanimuttar sub-basin forms an important groundwater province in south India, facing serious deficiency in both quality
and quantity of groundwater due to increased demand associated with rapid population explosion, agricultural growth and industrial
activities. A total of 194 groundwater samples were collected and 15 water quality parameters were analyzed using standard
procedures. Na + , Cl − , Ca2 + , HCO3-_{3}^{-}, Mg2 + and SO42-_{4}^{2-} concentration ions are more dominant in both seasons. The total dissolved solids and electrical conductivity was observed
good correlation with Na + , Cl − , HCO3-_{3}^{-}, Ca2 + , Mg2 + , Cl − , PO43-_{4}^{3-} and NO3- _{3}^{- } ions indicating dominance of plagioclase feldspar weathering, anthropogenic input and over drafting of groundwater irrespective
of seasons. The Hill–Piper diagram indicates alkaline earths exceed the alkalis, an increase of weak acids was noted during
both the seasons. For assessing the groundwater for irrigation suitability parameters like total hardness, sodium adsorption
ratio, residual sodium carbonate (RSC), permeability index, and sodium percentage are also calculated. Permanent hardness
was noted in higher during both the seasons due to discharge of untreated effluents and ion exchange process. The RSC indicates
56% of the samples are not suitable for irrigation purposes in both seasons, if continuously used will affect the crop yield.
From the results, nearly 72% of the samples are not suitable for irrigation. 相似文献
14.
Nagpur City located in semiarid area of central India is a fast-growing industrial centre. In recent years, rapid development
has created an increased demand for drinking water, which is increasingly being fulfilled by groundwater abstraction. The
present study was undertaken to assess major ion chemistry of shallow groundwater to understand geochemical evolution of groundwater
and water quality for promoting sustainable development and effective management of groundwater resources. A total of 47 water
samples were collected from shallow aquifer of selected parts of the city and the water chemistry of various ions viz. Ca2 + , Mg2 + , Na + , K + , CO3 2-_{3}^{\ \, 2-}, HCO3 -_{3}^{\ \, -}, Cl − , SO4 2-_{4}^{\ \,2-} and NO3 -_{3}^{\ \,-} are carried out. The chemical relationships in Piper diagram identify Ca–HCO3–Cl and mixed Ca–Na–HCO3–Cl as most prevalent water types. Alkaline earth exceeds alkalis and weak acids exceed strong acids. Ionic ratios and Gibb’s
diagram suggest that silicate rock weathering and anthropogenic activities are the main processes that determine the ionic
composition in the study area. The nitrate appeared as a major problem of safe drinking water in this region. We recorded
highest nitrate concentration, i.e., 411 mg/l in one of the dug well. A comparison of groundwater quality in relation to drinking
water quality standards revealed that about half of the shallow aquifer samples are not suitable for drinking. 相似文献
15.
Heavy metal pollution of water resources can be apprehended in East Singhbhum region which is a highly mineralised zone with
extensive mining of copper, uranium and other minerals. Ten groundwater samples were collected from each site and the heavy
metal analysis was done by atomic absorption spectrophotometer. Analysis of the results of the study reveals that the concentration
of iron, manganese, zinc, lead, copper and nickel in groundwater of Bagjata mining area ranged 0.06–5.3 mg l − 1, 0.01–1.3 mg l − 1, 0.02–8.2 mg l − 1, 1.4–28.4 μg l − 1, 0.78–20.0 μg l − 1 and 1.05–20.1 μg l − 1, respectively. In case of Banduhurang mining area, the range was 0.04–2.93 mg l − 1, 0.02–1.1 mg l − 1, 0.01–4.68 mg l − 1, 1.04–33.21 μg l − 1, 1.24–18.7 μg l − 1 and 1.06–14.58 μg l − 1, respectively. The heavy metals were found to be below the drinking water standards (IS:10500 1993) except iron (0.3 mg l − 1) and manganese (0.1 mg l − 1). The hazard quotients of the heavy metals for drinking water were below 1 posing no threat due to intake of water to the
people for both the areas. 相似文献
16.
Physico-chemical characteristics of some river and hand-dug well waters used for drinking and domestic purposes in the oil
rich Niger Delta area of Nigeria were assessed using standard methods. The concentrations of the parameters in the river water
samples ranged in the following order: pH (5.6–6.9), temperature (26.90–28.60°C), turbidity (23–63 NTU), electrical conductivity
(52–184 μs/cm), DO (5.4–7.2 mg/l), BOD (21–57 mg/l), TDS (6.0–217 mg/l), PO4
3− (0.19–1.72 mg/l), SO4
2− (25–36.8 mg/l), NO3
− (20.3–28 mg/l), Fe (6.07–15.71 mg/l), Zn (0.04–0.24 mg/l), Pb (0.01–0.17 mg/l), Ni (0.01–0.13 mg/l), Vn (0.01–0.20 mg/l)
and Hg (0.001–0.002 mg/l). The concentrations of these parameters in the hand-dug well water ranged in the following order:
pH (5.7–6.8) temperature (26–30°C), turbidity (134–171 NTU), electrical conductivity (160–340 μs/cm), DO (5.4–6.4 mg/l), BOD
(13–34 mg/l), TDS (110–190 mg/l), PO4
3− (0.84–1.84 mg/l), SO4
2− (10.6–28.1 mg/l), NO3
− (11.3–23 mg/l), Fe (13.17–16.31 mg/l), Ni (0.01–0.02 mg/l), Vn (0.01–0.04 mg/l) and Hg (0.001–0.004 mg/l). The concentrations
of BOD, turbidity, NO3
− and Fe in the water samples were above WHO and FMENV permissible limits for safe drinking water. The results suggest that
the use of such waters for drinking and domestic purposes pose a serious threat to the health of the users and calls for the
intervention of government agencies. 相似文献
17.
Estimation of Polish cigarettes contamination with cadmium and lead, and exposure to these metals via smoking 总被引:2,自引:0,他引:2
Galazyn-Sidorczuk M Brzóska MM Moniuszko-Jakoniuk J 《Environmental monitoring and assessment》2008,137(1-3):481-493
To estimate exposure to cadmium (Cd) and lead (Pb) through cigarette smoking, the concentrations of both metals in the blood
or/and urine of smokers (20 cigarettes or more per day for 10 years or longer) and their non-smoking counterparts inhabiting
an environmentally unpolluted area (Bialystok, Poland) were evaluated, as well as Cd and Pb contents in the cigarette brands
(produced in Poland) smoked by the participants, including intact cigarettes, pre-smoking (tobacco, paper and filter) and
post-smoking (butt, ash and smoke) cigarette components. Blood and urinary Cd concentrations in the smokers have been already
reported by us to be 2–4 times higher than in the non-smokers (Galażyn-Sidorczuk et al. Polish Journal of Environmental Studies,
13 (Suppl.1):91–95, 2004). All the other measurements are the subject of the present paper. Pb concentration in the blood of the cigarette smokers
(52.12 ± 15.51 μg l−1) was higher by 29% than in the non-smokers (40.42 ± 11.19 μg l−1). The mean Cd and Pb contents in the cigarettes were 0.6801 ± 0.1765 and 0.6853 ± 0.0746 μg per cigarette, respectively.
Under cigarette burning, performed using a machine for self-acting burning, on average 33% of Cd and 11% of Pb present in
the whole cigarette was released into the smoke. For Cd, unlike Pb, there was a high positive correlation between the metal
content in cigarettes and tobacco and its release into the smoke. Moreover, the subjects smoking cigarettes containing the
highest Cd amount had higher blood Cd concentration than smokers of other cigarette brands. The results give clear evidence
that in the case of inhabitants of areas unpolluted with Cd and Pb habitual cigarette smoking, due to tobacco contamination,
creates a serious source of chronic exposure to these metals, especially to Cd. 相似文献
18.
Padmalal D Remya SI Jyothi SJ Baijulal B Babu KN Baiju RS 《Environmental monitoring and assessment》2012,184(3):1541-1557
The southwestern coast of India is drained by many small rivers with lengths less than 250 km and catchment areas less than
6,500 km2. These rivers are perennial and are also the major drinking water sources in the region. But, the fast pace of urbanization,
industrialization, fertilizer intensive agricultural activities and rise in pilgrim tourism in the past four to five decades
have imposed marked changes in water quality and solute fluxes of many of these rivers. The problems have aggravated further
due to leaching of ionic constituents from the organic-rich (peaty) impervious sub-surface layers that are exposed due to
channel incision resulting from indiscriminate instream mining for construction-grade sand and gravel. In this context, an
attempt has been made here to evaluate the water quality and the net nutrient flux of one of the important rivers in the southwestern
coast of India, the Manimala river which has a length of about 90 km and catchment area of 847 km2. The river exhibits seasonal variation in most of the water quality parameters (pH, electrical conductivity, dissolved oxygen,
total dissolved solids, Ca, Mg, Na, K, Fe, HCO3, NO2-N, NO3-N, P
\text-inorg_{\rm \text{-}inorg}, P
\text-tot_{\rm \text{-}tot}, chloride, SO4, and SiO2). Except for NO3-N and SiO2, all the other parameters are generally enriched in non-monsoon (December–May) samples than that of monsoon (June–November).
The flux estimation reveals that the Manimala river transports an amount of 2,308 t y − 1 of dissolved inorganic nitrogen, 87 t y − 1 dissolved inorganic phosphorus, and 9246 t y − 1 of SO4, and 1984 t y − 1 K into the receiving coastal waters. These together constitute about 23% of the total dissolved fluxes transported by the
Manimala river. Based on the study, a set of mitigation measures are also suggested to improve the overall water quality of
small catchment rivers of the densely populated tropics in general and the south western coast in particular. 相似文献
19.
The main objective of this research was to estimate the total mass of nitrogen discharged from various sources in Korea using
the mass balance approach. Three different nitrogen mass balances were presented: (1) agricultural activities including raising
crops and animal husbandry; (2) domestic activities, and (3) activities in forest and urban areas. These nitrogen balances
were combined to estimate riverine discharge of nitrogen to the ocean in national scale. Nitrogen inputs include atmospheric
deposition, biological nitrogen fixation, application of inorganic fertilizers/manures, animal feed/imported foodstuffs, and
meat/fish. Nitrogen outputs include ammonia volatilization, denitrification, human/animal waste generation, crop/meat production,
and riverine discharge to the ocean. The estimated total nitrogen input in Korea was 1,194.5 × 103 tons N/year. Nitrogen discharged into rivers was estimated as 408–422 × 103 tons N/year, of which 66–71% was diffuse in origin. The estimated diffuse discharges for land uses were estimated as 82 × 103 tons N/year from agricultural areas, 7 × 103 tons N/year from forestry and 75 × 103 tons N/year from urban and industrial areas. 相似文献
20.
Liu CW Huang YK Hsueh YM Lin KH Jang CS Huang LP 《Environmental monitoring and assessment》2008,138(1-3):181-190
This study investigated total arsenic (As) and As species contents of oysters (Crassostrea gigas) in different production areas, seasons and sea locations on the southwestern coast of Taiwan. Analytical results indicate
that contents of total As, arsenite, arsenate, dimethylarsinic acid, monomethylarsonic acid and arsenobetaine in oysters are
9.90 ± 3.68, 0.091 ± 0.104, 0.033 ± 0.038, 0.529 ± 0.284, 0.037 ± 0.046 and 3.94 ± 1.33 mg/g (dry wt), respectively. A ratio
of inorganic As concentrations to total As concentrations is 1.26%. Total As contents of oysters cultured in the outer sea
are statistically significantly lower than those of oysters cultured in the inner sea. The total As contents of oysters is
the highest in Putai, where the blackfoot disease prevails. The low As contents in oysters is attributed to the low temperature
in winter, which slows the metabolism of oysters. A maximum value is 33.37 μg/g (dry) in Putai in spring, because a considerable
amount of aquacultural waste water with high As contents is discharged into adjacent drainage channels and rivers there during
that season. 相似文献