Holiday Schedule). We follow those guidelines. In addition, in October we provide all submitters with a schedule of when samples may be submitted during the Holiday season.
Q. WHAT ARE COLIFORMS? WHAT IS THEIR SIGNIFICANCE?
A. Coliforms are a type of intestinal bacteria that are used in assessing the quality of waters.
Q. WHAT IS ESCHERICHIA COLI? WHAT IS ITS SIGNIFICANCE?
A. Escherichia coli is a specific type of coliform. It is associated with warm-blooded vertebrate fecal contamination of water. There are designated limits on the numbers of this organism that may be found in waters depending on the intended use of the water.
Q. WHAT ARE ENTEROCOCCI? WHAT IS THEIR SIGNIFICANCE?
A. Enterococci are another group of intestinal organisms that are used to determine the microbiological quality of water. They are the mandated indicator organism to be used when assessing the quality of marine or estuarine water.
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Environmental Chemistry - MTBE
Q. What is Methyl Tertiary-Butyl Ether (MTBE) and what is its source?
A. Methyl tertiary-butyl ether, an oxygenate (a chemical that aids combustion by increasing available oxygen), is a synthetic organic compound which is colorless, flammable, volatile, has a turpentine-like odor, and is readily soluble in water.
It is a byproduct produced by combining methanol derived from natural gas and isobutylene during petroleum refinery processes.
Q. What is the purpose of adding MTBE to gasoline?
A. The purpose of adding MTBE to gasoline is to improve air quality. In 1990, the Clean Air Act was amended to require the use of reformulated (cleaner burning) gasoline to reduce vehicle tailpipe emissions, and thereby reduce ground level ozone. The use of MTBE boosts the oxygen content of the gasoline blend, producing a cleaner burning fuel which reduces carbon monoxide and hydrocarbons in vehicle emissions, greatly improving air quality.
Q. Why was MTBE the oxygenate of choice?
A. MTBE is the oxygenate of choice for several reasons. The production cost is low and it can be easily produced at the refinery. It blends easily with gasoline without separating. Also, MTBE gasoline blend can be transferred through existing pipelines without any modifications.
Q. How does MTBE enter the environment?
A. MTBE maybe present in many types of petroleum products in addition to gasoline. MTBE can be released into the environment when petroleum, liquid or vapor, is spilled or leaked. The most common spills or leaks occur at gas stations, other areas where gasoline is pumped into vehicles, near bulk gasoline loading and unloading facilities, other facilities with underground storage tanks, and when filling gasoline-powered home equipment and water crafts. MTBE can enter the environment through evaporation. Also, since it is readily soluble in water and does not bind well to soil, it makes its way into the ground and contaminates groundwater aquifers.
Q. What are the health effects of MTBE?
A. The U.S. EPA has tentatively classified MTBE as a possible carcinogen on the basis of studies that show this pollutant cause cancer in animals. However, there is no evidence that this pollutant can cause cancer in humans. According to published reports, human health effects of MTBE include, irritation to mucous membranes and respiratory tract, gastrointestinal disorders, and damage to the kidneys. The metabolites of MTBE, tertiary butyl alcohol and formaldehyde, have been classified by the EPA as being "probable human carcinogens".
Q. Are there other oxygenates that can replace MTBE?
A. The second most used fuel oxygenate is ethanol. Other oxygenated compounds that can be used include, methanol, ethyl tert-butyl ether, tert-amyl methyl ether, diisiopropyl ether and alkylates.
Q. What happens to MTBE in the environment?
A. The degradation of MTBE has two pathways: a microbial conversion in groundwater and a chemical conversion in the atmosphere. In groundwater, naturally occurring microbes degrade MTBE to tertiary butyl alcohol (TBA). In chemical degradation of MTBE, tertiary butyl formate is produced, which is then degraded to TBA. In both pathways, TBA is degraded to acetone and finally to carbon dioxide.
Q. Why does MTBE persist more in water than do other gasoline constituents?
A. MTBE is very soluble in water compared to other gasoline constituents such as benzene, toluene, ethyl benzene and xylene (BTEX compounds). The solubility of pure liquid MTBE in water is 50,000 mg/L, as compared to 1,780 mg/L for benzene, which is the next most soluble component of gasoline. In general, low solubilities indicate a strong partitioning to the subsurface solids. Hence, MTBE is less likely to adsorb to soil and more likely to persist in water, compared to other gasoline constituents.
Q. What analytical methods are used for the determination of MTBE in water?
A. Currently, DHMH - environmental chemistry laboratory analyzes MTBE in water samples using EPA Methods 524.2 and 8260 for the determination of volatile organic compounds using capillary column gas chromatography/mass spectrometry.
Q. How are samples collected and preserved for analysis of MTBE?
A. Samples are collected by registered sanitarians in 40ml glass vials with teflon-lined septum caps. They are preserved using either sodium thiosulfate or 1:1 HCl + ascorbic acid and are stored and transported to the laboratory at 4 oC. The prescribed holding time is 14 days.
Q. What regulatory guidelines have been issued for MTBE? Fdcb
A. Presently, there is no federal primary drinking water standard for MTBE, therefore, monitoring for its presence in drinking water is not required. The USEPA has recommended a drinking water advisory of 20 - 40 (g/L based on taste and odor thresholds.
On March 20, 2000, the federal government issued a regulatory advisory that would ban MTBE under the authority of the Toxic Substances Control Act (TSCA). This process can be lengthly and is expected to take at least five years.
Q. Who are the U.S. producers of MTBE?
A. The major U.S. producers of MTBE include ARCO Chemical, Texas Petrochemical, EGP (Enron), Global Octanes (Mitsui), Texaco Chemical, Ashland Oil, Amoco, Exxon Chemical, Phillips, Citgo, Mobil, and Sun Refining & Marketing. In 2001, U.S. production is estimated to average 200,000 barrels daily, roughly about 11 million gallons.
Q. What State/federal agencies can I contact for further information on MTBE?
A. Maryland Department of the Environment (email@example.com)
(Oil Control Program (410) 537-3386
(Voluntary Cleanup/Brownsfields Division (410) 537-3493
(Water Supply Program (410) 537-3714
(Water Quality Monitoring (410) 974-3238
(Superfund/CERCLA (410) 537-4888
(Hazardous Waste Enforcement Division (410) 537-3400
DHMH - Division of Environmental Chemistry (410) 767-4388
U.S. Environmental Protection Agency (800) 438-2474
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Virology and Immunology
CDC West Nile Questions and Answers
Q. What Do I Do When I Find A Dead Bird?
A. Click Here for the answer.
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Newborn and Childhood Screening Program
Q. WHAT IS THE NEWBORN SCREENING PROGRAM?
A. The Maryland Department of Health and Mental Hygiene offers newborn screening as a service to families with new babies. This program identifies newborn babies with certain rare, serious disorders of body chemistry. These disorders can be treated if detected early.
However, before your baby can be tested, you, as the parent, must agree. You may wish to discuss this issue with your spouse, another member, a friend, doctor, or nurse. We hope you will.
Q. WHY IS MY BABY TESTED?
A. The testing is done to help assure that your baby will be as healthy as possible. A simple quick and economical blood test provides important information about your baby's health that you or even your doctor might not otherwise know.
The Newborn Screening Program identifies the few infants who may have one of several rare disorders and alerts the doctors to this possibility. With early diagnosis and medical treatment, serious illness can usually be prevented.
Q. HOW IS MY BABY TESTED?
A. Once you give permission, your baby's heel will be pricked to get a few drops of blood. This blood will then be placed on special absorbent paper, dried, and mailed to the State Department of Health and Mental Hygiene Laboratory for examination. The laboratory needs just a tiny sample of blood to do all of the tests described in this brochure. The heel prick feels no worse than being stuck by a pin. Complications, such as infection of the heel, are very rare.
Q. WHAT ARE THE NAMES OF THESE DISORDERS?
Biotinidase deficiency (BI-oh-TIN-a-dase)
The body is unable to recycle the B vitamin called Biotin (BI-oh-TIN). Babies with this deficiency need more biotin than other babies. Treatment with extra biotin prevents the mental retardation and deafness that would otherwise result.
Branched chain ketoaciduria (KEE toe-acid-u-ree-ah)
This defect results from the body's inability to use some components (the branched chain amino acids) of food protein. This defect is also called maple syrup urine disease because the urine smells like maple syrup! This disorder is due to the lack of an enzyme (a chemical substance in the body). Treatment with a special diet can prevent life threatening complications.
Milk sugar (galactose) cannot be used by the body due to the lack of an enzyme. A diet low in galactose can prevent life-threatening complications.
Lack of an enzyme in the liver can produce mental retardation and body changes. A special diet can prevent mental retardation and other complications.
The body is unable to produce enough thyroid hormone (thyroxin) which leads to mental retardation and slow growth. This condition can be treated by giving thyroxin tablets.
Also called PKU. A component of food protein (phenylalanine) cannot be used by the body due to the lack of an enzyme. A special diet low in phenylalanine can prevent the brain damage that would otherwise result.
Sickle Cell Anemia
This is a serious blood disorder. Under certain conditions the abnormal blood cells can clog up the small blood vessels causing painful "crises." Babies with sickle cell anemia also have less resistance to infections, which may be life threatening. A regular treatment program using penicillin helps avoid serious complications.
Tyrosine, another component of the protein in food, cannot be used properly. This can result in a variety of complications including brain damage, and may be life threatening. Children with this disorder are treated with a special diet and in some cases with a liver transplant.
Work is still going on to develop tests for other serious disorders. Your baby may be tested for these as well. You will be told if any of these new tests suggests that your baby might have a problem.
From time to time, the state laboratory conducts studies on other important health problems using these specimens. These are only done after all the other tests are completed. These studies determine how many babies are affected by the problem being studied. They do not tell us whether individual babies have the problem, because the samples are not identified by name.
Q. BUT MY BABY SEEMS HEALTHY. ARE THE TESTS STILL NECESSARY?
A. Yes, the tests are necessary. Most infants with conditions identified by the Newborn Screening Program show no obvious signs of illness immediately after birth. However, each of these disorders can cause serious problems. If not found early and treated, all, except sickle cell anemia may cause brain damage and mental retardation.
THERE ARE MANY OTHER CAUSES OF MENTAL RETARDATION. We have only dealt with the few for which there are good screening tests. Poor growth, impaired vision, and lowered resistance to infection can also occur as a result of some of these disorders.
These disorders do not always show symptoms in the same way. Some babies may become dangerously ill within the first few weeks of life. Others may appear healthy for months or even the first few years of life. In either situation, serious harm is occurring that could be prevented with early treatment. Once the damage has occurred it can never be repaired.
Q. IS MY PERMISSION REQUIRED?
A. Most parents want to be informed about what is important to their baby's health so they can be sure that their child receives good care. Testing newborns for these disorders is an important part of good baby care.
The State of Maryland requires that you be asked for permission before the screening tests are done. You will receive a permission form after your baby is born. This will give you the chance to say "yes" or "no." Please, say 'YES'!
Q. HOW MUCH WILL THESE TESTS COST?
A. The State Laboratory charges the hospital a small fee for doing the tests on your baby’s blood sample. In addition, the doctor, clinic, or hospital may charge a small fee to do the heel prick.
Q. HOW DOES A BABY GET ONE OF THESE DISORDERS?
A. Except for hypothyroidism, a baby inherits the disorder from both parents. Parents and relatives usually show no sign of the disorder. In most cases of hypothyroidism the cause is not known. In a few, it is inherited.
These disorders are quite rare, and the chances are excellent that your child will not have one of them. The few children who are born with these problems are generally from healthy families. Testing EVERY baby after birth will make sure that each infant who has a disorder will be identified - and started on early treatment.
Q. WHEN IS THE BEST TIME TO TEST MY BABY?
A. We strongly recommend that each baby be tested twice.
The first test is usually done shortly before the baby leaves the hospital. For the most reliable results, it should be done after the baby has received at least 24 hours of breast or formula feedings.
In some cases, babies leave the hospital before they have had milk for 24 hours. They should be tested before they leave the hospital, but some of the test results will not be accurate because the baby hasn't yet had enough milk. The test should be repeated as soon as possible after the baby has had 24 hours of milk feedings. This will probably be the case by the time you take your baby to the doctor or clinic for his first check-up, which should be within the first two weeks of life. If your baby was not born in a hospital, the first test should be done at the first check-up, again, preferably within the first two weeks.
Most doctors will routinely obtain a second blood sample when the baby is a little older (4 to 6 weeks), even if the first test was ideal and normal. This second test just gives us another chance to find the babies with problems.
Q. HOW SOON WILL I KNOW THE RESULTS?
A. In most cases, the test results will be normal and you will not be notified. Your doctor or clinic will get the report when the tests are completed.
Results are usually available in about ten days. Generally, parents are notified only if there is a problem. You can ask about the results when you bring your baby to the doctor or clinic for a regular checkup.
Although "no news is good news," it is important to remember that these tests provide information only about the disorders that we have discussed. Even if your infant does not have one of these particular disorders, there may be other medical problems that cannot be picked up by these tests. Therefore, it is very important for your baby to have regular checkups and good general medical care.
Q. WHAT IF I AM TOLD THAT A RETEST IS NECESSARY?
A. Re-testing may be required for a number of good reasons. The most frequent reason is that the first sample contained too little blood to allow for completion all the tests. This does not mean there is anything wrong with the baby. It simply means that another sample must be obtained so that the complete set of tests can be performed.
On the rare occasions when the test indicates a possible problem, a new blood sample is requested, and the tests are repeated. As a general rule, only when one of the test results is abnormal for second time will the doctor discuss the need for further evaluation.
If you are asked to have your baby re-tested, please act quickly!
Q. WHAT IF MY BABY HAS ONE OF THESE DISORDERS? IS THERE A CURE?
A. Because most of these disorders are inborn problems of the body chemistry, they cannot be "cured" (just as eye color or height cannot be permanently changed). However the serious effects of the disorder can be lessened and often completely prevented by early treatment. The treatment is usually a special diet or medication. The health department or your doctor will make arrangements for referral and treatment.