Water, acid irrigation

Severe eye injuries from splashes may occur. In one case of eye burns from a fine spray of hydrofluoric acid in the face, considerable loss of epithelium occurred despite immediate and copious flushing with water and irrigation for 3 hours with a 0.5% solution of benzetho-nium chloride within 19 days, there was recovery of normal vision. ... 

Chemistry is for a large part conducted in solutions involving ions and such solutions are ubiquitous in nature. Oceans are vast aqueous solutions of salts, consisting mainly of sodium chloride, but other salts and minor components are also present in ocean water. Lakes, rivers, and brackish water are dilute solutions of ions and are essential to survival, since they provide drinking water and water for irrigation. Rain and other precipitates may remove ionic species from the atmosphere that arrived there as spray from oceans and seas or from human activities, for example, acid rain. Physiological fluids consist mostly of water in which colloidal substances, but also ions essential to their function, are dissolved. 

Antolfn MC, Santesteban H, Santa Maria E, Aguirreolea J, Sanchez-Diaz M (2008) Involvement of abscisic acid and polyamines in berry ripening of Vitis vinifera (L.) subjected to water deficit irrigation. Aust J Grape Wine Res 14 123-133... 

These acidic waters are toxic to plant and animal life, including fish and aquatic insects. Streams affected by acid drainage may be rendered nearly lifeless, their stream beds coated with unsightly yellow and red precipitates of oxy-hydroxide minerals. In some cases, the heavy metals in acid drainage threaten water supplies and irrigation projects. 

For concentrations below 10%, the evaporation of HF is reduced and direct contact with the liquid becomes the greatest risk. If HF is swallowed, it is advisable to drink lots of water, if possible with activated carbon added, in order to dilute the acid. Small amounts in the eye can cause intense irritation of the eyelids and slow ulceration of the conjunctivae. Large amounts in the eye cause immediate blindness. As first aid treatment the eyes should be irrigated immediately and copiously with clean water for a minimum of 15 min. Immediate medical care is mandatory after all the accidents mentioned above, even if no symptoms are apparent, because respiratory problems or other symptoms of poisoning can be delayed for hours after the incident has occurred. 

The half-life of acrolein in unsterilized supply water samples from an irrigation area was 29 h versus 43 h in thymol-treated water. A half-life of 43 h was also reported for acrolein in buffered distilled water at identical pH. These data suggest that biotransformation occurred in these aquatic systems. At higher aqueous concentrations (6.0 to 50.5 mg/L), the marked decrease in pH suggests that carboxylic acids were formed as end products (Bowmer and Higgins, 1976). 

Acidity-alkalinity of the solution, measnred as pH, is affected by the quality of the incoming water (generally acidic for rain, nentral or alkaline for irrigation and efflnents) and buffered by the environmental system. 

The penetration of hydrogen fluoride into the capillary cleft between the nail body and the nail bed is expecially hazardous because the acid cannot be removed by irrigation with water. In consequence, the nail has to be extracted if there is no response to direct injections into the nail bed. 

Boron (as boric acid) has a suggested international limit of 80 mg/liter. The probable source is soil or irrigation water, and several procedures are available for its determination. 

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