Estimation of Sediment Ingestion Rates Based on Hand-to-Mouth Contact and Incidental Surface Water Ingestion

2014 ◽  
Vol 21 (6) ◽  
pp. 1700-1713 ◽  
Author(s):  
Ross Wilson ◽  
Heather Jones-Otazo ◽  
Sanya Petrovic ◽  
Meghan Roushorne ◽  
Lindsay Smith-Munoz ◽  
...  
Keyword(s):  
Surface Water ◽  
Ingestion Rates ◽  
Water Ingestion

Epidemiological evidence of effects of EDC on ruminant reproduction

2001 ◽  
Vol 2001 ◽  
pp. 229-229
Author(s):  
Th.A.M. Kruip ◽  
G.A.L. Meijer ◽  
M. Boerjan
Keyword(s):  
Animal Model ◽  
Drinking Water ◽  
Surface Water ◽  
Dairy Cows ◽  
Direct Contact ◽  
Normal Surface ◽  
Dairy Farmers ◽  
Water Ingestion ◽  
Estrogen Exposure

Fifty percent of Dutch dairy farmers use surface water as the main source of drinking water for their cows during the grazing season. In many locations this surface water is in direct contact with a sewerage overflow. Belfroid and coworkers (1999) have demonstrated that this sewerage overflow surface water contains EDC, in particular xeno-oestrogens. The concentration of conjugated ethinyl-oestradiol, for example, in sewerage water was 0.02 mg/l. During the last decade the fertility of dairy cows has decreased dramatically. There is an increased incidence of cystic ovaries, an increase in the interval from calving to first insemination, an increase in the number of inseminations per pregnancy and more abortions have been recorded. These observations raise the possibility that EDC’s adversely affect reproduction in dairy cows. Meijer et al. (1999) compared the production and fertility of cows on 397 farms that used normal surface water with the production and fertility of cows on 60 farms that used water in direct contact with sewerage overflow. The results showed clearly that cows drinking water that was in direct contact with sewerage overflow produced less milk and had a greater age at first calving. Moreover they exhibited a tendency towards a longer interval between calving and first succesful insemination and tended to have a higher rate of abortions. Boerjan et al. (2001) have recently addressed the issues of concentrations of xeno-estrogens present in soil, in plants, in water and in cow tissues, milk and blood, in order to assess the potential risk to ruminants of xeno-estrogen exposure through soil and water ingestion. Although data are sparse and concentrations of EDC in feed and water of ruminant animals are low, under certain circumstances such as sewerage overflow and sludge-fertilized pasture, they concluded that rates of ingestion of certain xeno-oestrogens may exceed levels at which there is no effect. Since most EDC’s are lipophilic and become concentrated in adipose tissue, the mobilisation of fat during onset of lactation and pregnancy can expose animals to much higher concentrations of xeno-estrogens than are present normally in the environment. Important questions are: 1)how much of the EDC’s stored in fat cells will enter the blood under certain circumstances2)how much of the EDC’s in soil, water and plants will pass the rumen and enter also the blood and3)how potent are the different EDC’s i.e. what is the dose response relationship? In order to answer the last question an in vivo animal-model is urgently needed.We have developed an animal-model, based on the genital tract of an ovariectomized cow; the height and organisation of the endometrial lumen-epithelium, the rate of oedema in the stratum compactum and the electrical resistance of the cervical mucus are sensitive measures of oestrogenic activity.

Water Ingestion Rates

2015 ◽  
pp. 22-26
Author(s):  
Xiuge Zhao ◽  
Nan Huang ◽  
Chanjuan Zheng ◽  
Xianliang Wang ◽  
Beibei Wang ◽  
...  
Keyword(s):  
Ingestion Rates ◽  
Water Ingestion

Application of a Simple Cold Stub to the Direct Observation of Frozen Hydrated Sand

1973 ◽  
Vol 31 ◽  
pp. 212-213
Author(s):  
John M. Wehrung ◽  
Richard J. Harniman
Keyword(s):  
United States ◽  
Surface Water ◽  
Direct Observation ◽  
Controlled Study ◽  
Clay Particles ◽  
Organic Debris ◽  
Rock Formations ◽  
Water Tables ◽  
Permeable Rock ◽  
Natural Means

Water tables in aquifer regions of the southwest United States are dropping off at a rate which is greater than can be replaced by natural means. It is estimated that by 1985 wells will run dry in this region unless adequate artificial recharging can be accomplished. Recharging with surface water is limited by the plugging of permeable rock formations underground by clay particles and organic debris.A controlled study was initiated in which sand grains were used as the rock formation and water with known clay concentrations as the recharge media. The plugging mechanism was investigated by direct observation in the SEM of frozen hydrated sand samples from selected depths.

AN EVALUATION OF SUB-SURFACE WATER QUALITY AROUND BHARUCH-SURAT INDUSTRIAL REGION, GUJARAT, INDIA

2019 ◽  
Vol 38 (2) ◽  
pp. 200-220
Author(s):  
SOMNATH SAHA ◽  
◽  
SUKANTA KUMAR SAHA ◽  
TATHAGATA GHOSH ◽  
ROLEE KANCHAN ◽  
...  
Keyword(s):  
Water Quality ◽  
Surface Water ◽  
Surface Water Quality ◽  
Industrial Region
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