Archive for October, 2010

Highly Publicized Studies Link Cancer, DBPs

By Kendra Kozen | October 2010 Bookmark and Share Comments
Highly Publicized Studies Link Cancer, DBPs

Three recently released research papers that were played up in the national media have provided new insight on disinfection byproducts — and their potentially harmful effects.

The studies, spearheaded by researchers from the Barcelona-based Centre of Research in Environmental Epidemiology (CREAL) and Research Institute Hospital del Mar and the U.S. Environmental Protection Agency, present a comprehensive analysis of disinfection byproducts and provide more findings that correlate certain byproducts of chlorine sanitizers with respiratory problems and bladder cancer, particularly in indoor aquatic environments.

“We examined for the first time in a real-life situation whether some of the chemicals present in pool water could be harmful to our health,” said researcher Manolis Kogevinas, MD, PhD, professor of epidemiology at the Centre for Research in Environmental Epidemiology in Barcelona.

Some of these chemicals have been tested in the lab and with experimental animals and some have been shown to be toxic. However, finding a toxic effect in the lab does not mean necessarily that it is associated with adverse health effects in humans, researchers caution.

The first study included 49 healthy adults; subjects swam for 40 minutes in an indoor chlorinated pool. Both before and afterwards researchers collected blood, urine and exhaled air samples to test for biomarkers linked to cancer. The culprit in the cancer issue is a chemical compound class called trihalomethanes. According to the findings, “after swimming, the total concentration of the four trihalomethanes in exhaled breath was seven times higher than before swimming.”

“What we found is by analyzing blood samples and urine samples, we have an increase in risk markers related to cancer,” Dr. Kogevinas explained in an article published on WebMD.

Above certain exposure levels, THMs have been scientifically shown to lead to cancer in people and animals, said Ed Lightcap, a senior account manager at DuPont Chemical in Wilmington, Del. “In humans, bladder cancer seems to be the most common manifestation,” he noted. Though water-transmitted THMs have been linked to bladder cancer in previous studies, Lightcap added, “typically [it’s discussed] in relation to shower water. Lately, some research has been focusing on pools, too.”

The second study included 48 adult swimmers from the same group. Researchers compared markers of lung injury before and after participants swam for 40 minutes and found an increase in one blood biomarker that could indicate a correlation between asthmatic symptoms and lung damage with inhalation of chloramines in indoor pool environments. But according to the study more research is needed to confirm the results and understand long-term impact. There are also questions over whether results were due to the physical activity itself, rather than exposure to disinfection byproducts.

“Oxidative stress [during exercise] will cause damage to certain lung cells,” said Thomas Lachocki, Ph.D., CEO of the National Swimming Pool Foundation in Colorado Springs, Colo. “But that’s normal, and even positive in many ways. And the body is continually repairing that damage.”

The final study in the trio was an effort to better understand the makeup of DBPs. Using several methods of analysis researchers identified more than 100 DBPs, many containing nitrogen (likely formed from organic matter from humans) and many never before identified DBPs.

All three studies were published online in the journal Environmental Health Perspectives and the findings were picked up by major news organizations, which left some industry professionals displeased with the coverage.

“Some in the media jumped hastily to suggest alternatives to chlorination for disinfecting swimming pools that might impact public health adversely,” said Judith Nordgren, Managing Director of the American Chemistry Council’s Chlorine Chemistry Division. While follow up work is needed, pool operators can minimize any potential risk by optimizing their water quality and minimizing use of chemicals where possible, and educating patrons on healthy swimming behaviors said Dr. Kogevinas and Susan Richardson, Ph.D, a research chemist with the U.S. Environmental Protection Agency who was also a lead researcher on the final study.

Resevoir Aeration

http://www.epaeration.com/products_services.php

Made in San Luis Obispo, CA U.S.A with the best compressors and ozone generators available, all E P Aeration reservoir systems run on 120VAC, 20A household current. Compressors and ozone units are incredibly simple and inexpensive to maintain, generally requiring less than two hours per year to service. Internally cooled and weatherproof, E P Aeration units can be wall mounted or stand alone, indoor or outdoor.

The heart of the E P Aeration system is the patented tubing which we use for all of our applications. Whether it’s wastewater or a decorative water feature we use the same style of air diffusion, it’s just a matter of scale.

Ozone Aeration Cabinet Interior
Ozone Aeration Cabinet Exterior
The EP-2006 Uni-2 (shown above left and larger unit on right) consists of two 1/3rd horsepower air compressors generating a total of 9 CFM of air mixed with 4 grams/hr. of ozone. Equipment runs on 120V, 20A power supply and is housed in an internally cooled and weatherproof enclosure. This system is perfect for water bodies 1-2 acres in surface area.
THE E P AERATION DIFFERENCE
With E P Aeration you’re buying the best:
  • The best ozone generators
  • The best air-diffusion tubing
  • The best compressors available
  • The best bio-remediation products
  • The best artificial littoral zone products
  • The best shade and coloring products

Yet the E P Aeration difference is more than just equipment – it’s the experience we’ve gained in aerating lakes, ponds, and water features of all descriptions, in all sorts of climates, for more than 20 years. When we recommend a solution for your water problems, you can be sure that you’re getting more than a one-size-fits-all type of answer – you’re getting the E P Aeration difference.
E P Aeration utilizes bottom laid, fine bubble aeration:

  • Increasing dissolved oxygen levels throughout the water column
  • Eliminating thermal stratification

Because our lake and pond systems use standard household current (120 VAC, 15-amp circuit), and because we pump air, not water, our customers realize significant savings in installation, operation and maintenance costs. Our current, modular systems are the result of more than 10 years of development, and more than 20 years of ozone generation and lake and pond aeration experience. The modular nature of the systems allows us to recommend the most effective – and cost effective – solutions for your water problems.

THE HEART OF LAMINAR FLOW TECHNOLOGY™ IS THE PATENTED TUBING
E P Aeration utilizes proprietary air-diffusion tubing in its lake and pond ozonation/aeration system modules. In use for more than 45 years in the wastewater treatment industry, this keel-weighted, bottom-laid tubing features the highest documented oxygen transfer rates in the business. The keel weighting ensures that the tubing lies on the bottom, at the sludge layer, with the air release slits always upright.
Available with air release slits cut on 6-inch centers, 3-inch centers, and 1 ½-inch centers, the tubing can also be manufactured in “triple cut”, or three air release slits at each position, for more demanding jobs, as in wastewater treatment. The air release slits are precisely cut to produce a calculated bubble size and rate of rise (no more than .8 ft. per second). No other air diffusion system, including competitive tubing, has the proven performance of that used by E P Aeration, which is why it was selected originally more than 20 years ago, and why it is still in use today.
The precise cut, and material memory ensure that the slits only open with 2 psi or more of pressure, and close immediately on shut-down. This ensures that minimal amounts of water and/or dirt can enter the tubing, minimizing cleaning and maintenance.

Aeration Tubing
Made of low-density polyethylene copolymer with 2% carbon black for ultraviolet stabilization, the tubing has an interior diameter of .5″.
The tubing meets or exceeds Federal Specification L-P-3906, REA PE-200, and ASTM D1248.
Although E P Aeration system modules often utilize tubing laid in a straight line on the bottom at the deepest part of the water feature,
the tubing is also available on custom-made stainless steel diffusion disks (shown below & right) for deep holes or unusual lake or pond configurations.

Moore's Lake Bubble Plume
DM-LTC Air Diffuser
The River Course at the Alisal, Solvang, CA was one of the first eco-friendly golf courses. The River Course was designed with leachate systems under the greens and other runoff-recapture features to avoid polluting the Alisal River, along which it was built.
Stainless steel disk module

Why Ozone…?

  • Dissolves into water 13 times faster than O2
  • Kills viruses, bacteria, molds, spores, and cysts up to 3000 times faster than chlorine
  • Keeps the inside of bottom-laid tubing clean and maintenance free
  • Oxidizes organic nutrients, chlorohydrocarbons
  • Precipitates iron, manganese, and heavy metals from water
  • Produces increased water clarity
  • Has been shown to affect soil absorption rates of salts and other compounds

E P Aeration systems generate ozone in two ways, each of which mimics the way ozone is produced in nature. Generally, our lake and pond systems utilize ultraviolet light to produce the small amounts of ozone appropriate to that application. In our recirculation, closed-loop water treatment systems, we utilize corona-discharge (high-voltage electricity) generators, which produce larger quantities of ozone which are usually injected directly into the recirculation or pump system. The availability of both types of ozone generators and the modular nature of our systems allows us to customize systems recommendations to solve the myriad of specific problems possible in a wide range of applications.
The use of ozone in most lake and pond applications is not intended to “kill algae” or sterilize the water feature. Instead, our lake and pond systems are designed to:

  • Address the Biochemical Oxygen Demand (BOD) of the water with Aeration
  • Use ozone to increase oxygenation in the water
  • Oxidize hydrogen sulfide
  • Precipitate out certain metals and suspended solids
  • Keep the aeration tubing clean and maintenance-free

Of course, if circumstances demand larger quantities of ozone, we have the capabilities of meeting such demand with corona-discharge ozonators.
E P Aeration‘s aeration/ozonation systems are compatible with other non-chemical strategies, such as the use of bio-augmentation/remediation systems. While it is true that ozone will kill bacteria, (even beneficial ones) on contact, only a small number of sludge-eating bacteria, for example, might come into contact with the ozone at the point of bubble release. Ozone, with a half-life of 30 minutes in pure, distilled water, will usually be consumed by other substances in the water, and never reach the surface to be re-circulated. Increased oxygen at the sludge level is a positive environmental situation for micro-organisms and other small forms of life.
Ozone’s primary byproduct is oxygen. Ozone is unstable, and does not produce a long-term residual. It is an important adjunct component in our lake and pond aeration systems. Ozone is an appropriate primary treatment for closed-loop and/or recirculation systems.

Consumer Products

Aeration Cabinet

The EP-AO1 Mini is a consists of a 1/3rd horsepower air compressor inside of an interanally cooled NEMA 4 rated cabinet. This unit can be wall or post mounted (shown above) and is perfect for ponds 1/5 – 1 acre in surface area or for tank aeration. Pair this unit with a LTC Disk module and circulate up to 12 million gallons of water per day.


Aeration Cabinet

An AO-1 Mini in the field at an equestrian ranch in Paso Robles, CA. This unit is used to aerate a 1/5 acre water feature used for swimming and fishing. Considered “country quiet” this unit operates at less than 55 decibals and is located 100 yards from the pond ensuring that the pond edge is a quiet and peaceful place to lounge, swim, or fish.

 

Bacta Pur

E P Aeration is a proud distributor of Bacta-Pur beneficial bacterial products for water treatment. Bacterial supplements are available for an array of water treatment purposes including water clarity, sludge digestion, and nutrient control. We also carry shades and colorants for enhanced algae control and aesthetics.

 

E P Aeration has a full line of supplementary products for bioremediation, color and shade.

Bacta-Pur%20logo%20copy

 

Outdoor-Water-Solutions-Bla Windmill Aeration Windmill Aeration

E P Aeration is proud to offer wind-powered aeration using Outdoor Solutions windmills. The windmills come in different sizes and colors. A company logo can be placed on the tail fin, as in the John Deere photo on the right. These devices are ideal for use in water features where electric power is unavailable or impractical.
AquaMats
E P Aeration utilizes AquaMats in many installations where an artificial littoral zone needs to be established. Beneficial organisms colonize the AquaMats as they would with water plants and reeds, providing important filtering functions to a lake or pond.

Floating-Wetland-at-Jordan-

E P Aeration has developed and tested their own line of floating wetlands for enhanced water treatment and biodiversity. Using a process called “fixed film media”, floating wetlands not only contain nutrient consuming wetland plants, they host a nitrifying and denitrifying bacteria on their roots that grow down through the water column. These bacteria consume nutrients while providing food for fish and other organisms that like to make the islands their homes. Note the aeration bubbles in the background ensuring that the roots of these plants are always in highly oxygenated conditions.

OSEC®-NXT Membrane Electrochlorination System

http://www.water.siemens.com/en/products/chemical_feed_disinfection/hypochlorite_generation/Pages/osec_nxt.aspx

The series of OSEC®-NXT membrane electrochlorination systems is used for commercial leisure and swimming pool applications as well as potable or industrial water treatment.

OSEC-NXT Membrane Electrochlorination System
OSEC®-NXT System

They provide many safety features when used as an alternative to chlorine gas systems. Transport and handling of chlorine cylinders is completely eliminated. Only saturated brine and softened water are needed for the redeveloped electrolyzer process which safely and efficiently produces hypochlorite on-site. The optimized efficiency of the electrolyzer cells leads to a minimum demand for brine and power.

The integrated Wallace & Tiernan® ChemWeb-Server data communication server provides remote visualization capability. All components for the electrolyzer process, the controller, and the water softener are skid mounted for easy installation while maintaining a small foot print. In addition, the lower capacity systems up to 6 kg (13 lb) per day contain integrated tanks for brine and sodium hypochlorite.

Chlorine Dioxide

from Lenntech

What are the advantages of the use of chlorine dioxide?

Advantages
The interest in the use of chlorine dioxide as an alternative for or addition to chlorine for the disinfection of water has increased in the last few years. Chlorine dioxide is a very effective bacterial disinfectant and it is even more effective than chlorine for the disinfection of water that contains viruses. Chlorine dioxide has regained attention because it is effectively deactivates the chlorine-resistant pathogens Giardia and Cryptosporidium. Chlorine dioxide removes and prevents bio film.
Disinfection with chlorine dioxide does not cause odor nuisance. It destroys phenols, which can cause odor and taste problems. Chlorine dioxide is more effective for the removal of iron and manganese than chlorine, especially when these are found in complex substances.

Does chlorine dioxide form chlorinated disinfection byproducts?
The use of chlorine dioxide instead of chlorine prevents the formation of harmful halogenated disinfection byproducts, for example trihalomethanes and halogenated acidic acids. Chlorine dioxide does not react with ammonia nitrogen, amines or other oxidizable organic matter. Chlorine dioxide removes substances that can form trihalomethanes and improves coagulation. It does not oxidize bromide into bromine. When bromide containing water is treated with chlorine or ozone, bromide is oxidized into bromine and hypobromous acid. After that these react with organic material to form brominated disinfection byproducts, for example bromoform.

Is the chlorine dioxide concentration needed for sufficient disinfection high?
The use of chlorine dioxide reduces the health risk of microbial pollutions in water and at the same time decreases the risk of chemical pollutions and byproducts. Chlorine dioxide is a more effective disinfectant than chlorine, causing the required concentration to kill microorganisms to be much lower. The required contact time is also very low.

Does the pH value influence chlorine dioxide efficiency?
Contrary to chlorine, chlorine dioxide is effective at a pH of between 5 and 10. The efficiency increases at high pH values, while the active forms of chlorine are greatly influenced by pH. Under normal circumstances chlorine dioxide does not hydrolyze. This is why the oxidation potential is high and the disinfection capacity is not influenced by pH. Both temperature and alkalinity of the water do not influence the efficiency. At the concentrations required for disinfection, chlorine dioxide is not corrosive. Chlorine dioxide is more water-soluble than chlorine. In the last few years better and safer methods for chlorine dioxide production have been developed.

Figure 3: the influence of pH on efficiency is larger for chlorine than for chlorine dioxide

Can chlorine dioxide be used combined with other disinfectants?
Chlorine dioxide can be used to reduce the amount of trihalomethanes and halogenated acidic acids, formed by the reaction of chlorine with organic matter in water. Before the water is chlorinated, chlorine dioxide is added. The amount of ammonium in the water decreases. The chlorine that is added afterwards, oxidizes chlorite into chlorine dioxide or chlorate. Ozone can also be used to oxidize chlorite ions into chlorate ions.
By the use of chloramines, nitrification can take place in the distribution network. To regulate this, chlorine dioxide is added.
Byproducts control by chlorine dioxide can take place in combination with adequate disinfection, especially the reduction of bromine containing trihalomethanes and halogenated acidic acids that originate from the reaction of bromine containing water with natural organic matter. Chlorine dioxide itself combined with bromine does not form hypobromous acid or bromate, while chlorine and ozone do. Chlorine dioxide has excellent anti-microbiological qualities without the non-specific oxidation of ozone.

What are the disadvantages of the use of chlorine dioxide?

Is chlorine dioxide explosive?
When producing chlorine dioxide with sodium chlorite and chlorine gas, safety measures must be taken with regard to the transport and use of chlorine gas. Sufficient ventilation an gas masks are required. Chlorine dioxide gas is explosive.
Chlorine dioxide is a very unstable substance; when it comes in contact with sunlight, it decomposes.
During chlorine dioxide production processes, large amounts of chlorine are formed. This is a disadvantage. Free chlorine reacts with organic matter to form halogenated disinfection byproducts.

Does chlorine dioxide form byproducts?
Chlorine dioxide and its disinfection byproducts chlorite and chlorate can create problems for dialysis patients.

Is chlorine dioxide effective?
Chlorine dioxide is generally effective for the deactivation of pathogenic microorganisms. It is less effective for the deactivation of rotaviruses and E. coli bacteria.

What are the costs of chlorine dioxide use?
Chlorine dioxide is about 5 to 10 times more expensive than chlorine. Chlorine dioxide is usually made on site. The costs of chlorine dioxide depend upon the price of the chemicals that are used to produce chlorine dioxide. Chlorine dioxide is less expensive than other disinfection methods, such as ozone.

What are the health effects of chlorine dioxide?

Chlorine dioxide gas
While using chlorine dioxide as a disinfectant, one has to keep in mind that chlorine dioxide gas can escape from a watery solution containing chlorine dioxide. Especially when disinfection takes place in a sealed space, this can be dangerous. When chlorine dioxide concentrations reach 10% or more in air, chlorine dioxide becomes explosive.
Acute exposure of the skin to chlorine that originates from the decomposition of chlorine dioxide, causes irritations and burns. Eye exposure eyes to chlorine dioxide causes irritations, watering eyes and a blurry sight. Chlorine dioxide gas can be absorbed by the skin, where it damages tissue and blood cells. Inhalation of chlorine dioxide gas causes coughing, a sore throat, severe headaches, lung oedema and bronchio spasma. The symptoms can begin to show long after the exposure has taken place and can remain for a long time. Chronical exposure to chlorine dioxide causes bronchitis. The health standard for chlorine dioxide is 0,1 ppm.

Development and reproduction
Chlorine dioxide is thought to have effects on reproduction and development. However, there is too little evidence to ground this thesis. Further research is required.

Mutagenity
The Ames test is used to determine the mutagenity of a substance. The Ames test uses Salmonella bacteria that are genetically modified. No bacterial colonies are formed, unless they come in contact with a mutagenic substance that alters genetic material. Tests show that the presence of 5-15 mg/L ClO2 increases the mutagenity of water. It is difficult to prove the mutagenity of chlorine dioxide and chlorine dioxide byproducts, because the substances are biocides. Biocides usually kill the indicator organisms that are used to determine mutagenity.

Read more: http://www.lenntech.com/processes/disinfection/chemical/disinfectants-chlorine-dioxide.htm#ixzz136BgOznI

Can chloramines be removed from water?

from Lenntech

Chloramines remain active in the water system for a considerably long period of time. Like other molecules, chloramines contribute to the total amount of dissolved solids in the water. Like chlorine, chloramines are selectively reactive and may have damaging affects when they remain in the water for too long.
When chloramines are present, there are usually trace amounts of ammonia and hypochlorite in the water as well. Chloramines are hardly ionic. As a result and because of the low molecular weight, chloramines, mainly monochloramine, are difficult to remove from water by reverse osmosis (RO) or water softening. Boiling and distillation cannot be used either. Substances for chlorine removal cannot be used for the removal of chloramines. Sunlight and aeration may aid chloramine removal.
Chloramines can be removed by means of a granular active carbon filter. This filter brings down chloramine concentrations from 1-2 ppm to less than 0,1 ppm. One must make sure that the active carbon comes in contact with chloramines for a significant amount of time. An active carbon filter is a selective, which means it also removes other compounds, such as chlorine (reduction to chloride), hydrogen sulphide, organic compounds, THM, pesticides and radon. When these compounds are present in water, this will influence the capacity of the filter.
The amount of chloramines in the water can be determined by measuring the ‘total chlorine’ residu. This means measuring the ‘total amount of chlorine’ or the ‘amount of chlorine compounds’.

Read more: http://www.lenntech.com/processes/disinfection/chemical/disinfectants-chloramines.htm#ixzz13681GRJc