how does lead and/ or mercury get into our water systems ?
831727
Both are present in small amounts in soils and rocks.  Spillage from waste dumps can be a source also.
751361
Mercury is toxic in several ways.\nAt room temperature is gives off a vapour (which can be seen if you shine an ultra-violet light onto a screen in front of which is a bowl of mercury). As a vapour it is quickly absorbed through the lungs.\nIt is absorbed through the skin but very slowly. Only a small proportion is absorbed by the digestive system if the metal is swallowed. You would have to take almost a table-spoon full to make you seriously ill or kill.\nMercury compounds are seriously poisonous especially soluble ones like the chloride. Organo-mercury are the worse as they are very readily absorbed into the tissues of the body.\nMercury is very good at replacing the trace metal elements in the body such as copper, cobalt, chromium etc. At autopsy it can be found in almost every tissue in the body.\nIt is slowly eliminated from the body taking about 70 days for half of it to leave and another 70 days for half of the remaining to go.\nIt causes a whole host of illnesses from loosening of teeth, mental disturbance and organ failure.
56978
water, water and more water
422197
with plates of lead and an acid.
112035
As everyone knows by now, lead is poisonous. That is why we don't make lead pipes any more for plumbing (one of the potential reasons the Roman empire fell), or use tetraethyl lead to increase octane number in gasoline, or use lead-based paints. \n\nHowever, it is less well-known that lead is often radioactive. Natural lead is a mixture of four stable isotopes: 204Pb (1.48%), 206Pb (23.6%), 207Pb (22.6%), and 208Pb (52.3%). These lead isotopes are the result of the decay of uranium (Pb206), actinium (Pb207) and thorium (Pb208). There are also another 27 other radioactive isotopes of lead that are possible, but if they are present naturally, they are present only in tiny amounts. \n \n\n\nPb204 is only very slightly radioactive, with a half-life of 1.4e17 years (longer than the present age of the universe). Pb205 does not occur naturally, and has a half life of 1.53e7 years. Pb206, Pb207 and Pb208 are not at all radioactive. Pb210 is only present in trace amounts in the natural environment, and has a half life of 22.3 years. The decay products are alpha particles and beta particles, both of which are easily blocked (in contrast to gamma radiation).\n\nRecently, the State of Illinois determined that some products made with lead were contaminated with radioactive lead (see attached reference). However, on studying the problem, both the state of Illinois and the EPA decided that the hazards due to radiation were very limited.\n\nRemember, one increases substantially ones exposure to radiation by taking a plane flight, or by moving to Denver. The increase in radiation exposure has to be balanced against what is present in the natural environment. \n\nAlso, it is not clear how dangerous low levels of radiation are. There is a concept called radiation hormesis that has been around for a long time, but is now being reexamined carefully again. It is possible that small doses of radiation might be helpful in some cases (see reference).
431187
i think most tap water contains fluoride, something bottled water companies filter out. seems that tap water is actually more regulated than bottled water.
22021
Considering our water these days you just have to consider two factors (A) its salty (B) its most likely dirty.\n\nEffects of drinking contaminated water:\nhttp://www.walrus.com/~gatherer/interpret.html#health
313922
Yes there is.  If there is any lead in your pipes anywhere, it will leach into hot water to a much higher degree than it would in cold water. (Think of what happens to a tea bag in hot water as opposed to cold.)  Lead is very, very bad for your brain.  Also, if the pipes are plastic, plastic leaches more easily in heat as opposed to cold. (Manufacturers of plastic food wrap/containers tell you to NOT microwave food in plastic!) And, by the way, have you ever drained your water heater and seen what comes out of it?  Yuck!
1117721
No, there is no Lead (Pb) in water (H2O)
481463
there are a variety of treatment options depending on the type of pollution. \nboiling is only effective for biological contamination\nmembrane filtration will eliminate heavy metals\nDistillation will remove everything but is very expensive\naeration is effective for volatile organic compounds
167637
Although it might seem convenient to make up formula from warm tap water, this is not safe according to the U.S. Environmental Protection Agency (EPA). Compared with cold tap water, warm water is far more likely to carry lead that has leached out from the plumbing. Lead levels in drinking water tend to be highest in homes built before 1930 with lead pipes; homes less than 5 years old with copper pipes and lead solder, and homes with brass faucets or fittings.
250594
This is an Internet myth.  Lead in pipes (water pipes)_ is a hazard.  Lead in pipe organs is not.  The law you are worried about does not exist.
933095
Well water can over time through a process called weathering, other than that acid is excellent, that is how acid rain is effecting us.\nAlso salt and a number of other chemicals and solvents.
1143109
lead, poisonous gas emmissions...you are talking about damage...this stuff can kill you
69020
The simple answer:\nMercury is absorbed into the tissue of the organism where where it cannot be purged quickly and therefore it accumulates. \n\nA more complicated answer:\nAbsorbed mercury, causes the solution of mercury compounds in sodium chloride facilitating their transformation into complex compounds, shloroalbuminates. The latter are large complex molecules, in which mercury preserves its ionized state and carries a positive electrical charge.
961939
The weights of the liquids inside 2 branches must be equal, therefore:\n\na) m_water + m_oil = m_mercury (the amount of mercury that raised in the other branch to keep the balance)\n\nm_water = D_water * V_water = D_water * h_water * Area\nm_oil = D_oil * V_oil = D_oil * h_oil * Area\nm_mercury = D_mercury * V_mercury = D_mercury * h_mercury * Area\n\nSubstitute this in the balance of weights above, we have\nD_water * h_water * Area + D_oil * h_oil * Area  = D_mercury * h_mercury * Area\n<-> h_mercury = (D_water * h_water + D_oil * h_oil) / D_mercury\n\nb) To bring mercury's surface two the same level again, the weight of the to-be-added water must be the same with the weight of both oil and water in the other branch.\n\nYou can do the same as above to find:\nh_water2 = (D_water * h_water + D_oil * h_oil) / D_water
831216
Cu (s) + Pb(NO3)2 (aq) ---------> No Reaction. \nCopper will not replace lead.\n\nreaction VI in the attached link.