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Reef Safe Plastics & Leaching (myths&facts) - 3reef Forums
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infamous 3reef Forums
This topic came up when someone in my reefclub posted a thread about plastic autotopoff container and which one should be used. Everyone in the reefclub jumped on it suggesting #1 or #2 plastics.
I decided to do some more research on the topic because i noticed that no one ever gave any other reason why people should use those platics other than that they were food grade plastics and are not recycled . So i did some searching around and realized that people had no idea why they were recommending those types of platics.
Myth:The higher number on the plastic means its better quality or is more pure.
Fact: The number on the plastic has nothing to do with the quality or purity. It tells you the chemical makeup of the polymers used in the plastic and the optimal use of that plastic. The number also tells us what that plastic can be recycled into.
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Myth:#1 and #2 are food grade plastics and are better.
Fact:Many plastics are food grade plastics. #1, #2, #5, #6 and #7. For example baby bottles are typically made from #7 plastic.
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Myth:The recycle logo means that the plastic has some recycled material added to it.
Fact:The logo means that the item
can be recycled and number in the middle also tells us what kinds of things that plastic can be recycled to.
If the item has recycled material, it will say so in print.
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Myth: Plastics can leach just like any other material.
Fact:Most plastics don't leach toxic substances. Once the plastic is hard, it only mixes with substance of similar macromolecular structure. Even if you heat it, it still won't mix with water or saltwater. However, some plastics
(Namely #1 and #7 plastics) have been known to leach traces of toxic substances when exposed to microwaves or superhot liquids(water,milk etc).
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You will typically find these logos on plastic containers.
What do the numbers mean and what are those letters at the bottom?
Number 1 Plastics -- PET or PETE (polyethylene terephthalate)
* Found In: Soft drinks, water and beer bottles; mouthwash bottles; peanut butter containers; salad dressing and vegetable oil containers; ovenable food trays.
* Recycling: Pick up through most curbside recycling programs.
* Recycled Into: Polar fleece, fiber, tote bags, furniture, carpet, paneling, straps, (occasionally) new containers
It poses low risk of leaching breakdown products. Recycling rates remain relatively low (around 20 percent), though the material is in high demand by remanufacturers.
Number 2 Plastics -- HDPE (high density polyethylene)
* Found In: Milk jugs, juice bottles; bleach, detergent and household cleaner bottles; shampoo bottles; some trash and shopping bags; motor oil bottles; butter and yogurt tubs; cereal box liners
* Recycling: Pick up through most curbside recycling programs, although some only allow those containers with necks.
* Recycled Into: Laundry detergent bottles, oil bottles, pens, recycling containers, floor tile, drainage pipe, lumber, benches, doghouses, picnic tables, fencing
HDPE carries low risk of leaching and is readily recyclable into many goods.
Number 3 Plastics -- V (Vinyl) or PVC
* Found In: Window cleaner and detergent bottles, shampoo bottles, cooking oil bottles, clear food packaging, wire jacketing, medical equipment, siding, windows, piping
* Recycling: Rarely recycled; accepted by some plastic lumber makers.
* Recycled Into: Decks, paneling, mudflaps, roadway gutters, flooring, cables, speed bumps, mats
PVC contains chlorine, so its manufacture can release highly dangerous dioxins. If you must cook with PVC, don't let the plastic touch food. Never burn PVC, because it releases toxins.
Number 4 Plastics -- LDPE (low density polyethylene)
* Found In: Squeezable bottles; bread, frozen food, dry cleaning and shopping bags; tote bags; clothing; furniture; carpet
* Recycling: LDPE is not often recycled through curbside programs, but some communities will accept it. Plastic shopping bags can be returned to many stores for recycling.
* Recycled Into: Trash can liners and cans, compost bins, shipping envelopes, paneling, lumber, landscaping ties, floor tile
Historically, LDPE has not been accepted through most American curbside recycling programs, but more and more communities are starting to accept it.
Number 5 Plastics -- PP (polypropylene)
* Found In: Some yogurt containers, syrup bottles, ketchup bottles, caps, straws, medicine bottles
* Recycling: Number 5 plastics can be recycled through some curbside programs.
* Recycled Into: Signal lights, battery cables, brooms, brushes, auto battery cases, ice scrapers, landscape borders, bicycle racks, rakes, bins, pallets, trays
Polypropylene has a high melting point, and so is often chosen for containers that must accept hot liquid. It is gradually becoming more accepted by recyclers.
Number 6 Plastics -- PS (polystyrene)
* Found In: Disposable plates and cups, meat trays, egg cartons, carry-out containers, aspirin bottles, compact disc cases
* Recycling: Number 6 plastics can be recycled through some curbside programs.
* Recycled Into: Insulation, light switch plates, egg cartons, vents, rulers, foam packing, carry-out containers
Polystyrene can be made into rigid or foam products -- in the latter case it is popularly known as the trademark Styrofoam. Evidence suggests polystyrene can leach potential toxins into foods. The material was long on environmentalists' hit lists for dispersing widely across the landscape, and for being notoriously difficult to recycle.
Number 7 Plastics -- Miscellaneous
* Found In: Three- and five-gallon water bottles, 'bullet-proof' materials, sunglasses, DVDs, iPod and computer cases, signs and displays, certain food containers, nylon
* Recycling: Number 7 plastics have traditionally not been recycled, though some curbside programs now take them.
* Recycled Into: Plastic lumber, custom-made products
So which plastics leach and which are safe to use in reef tanks?
I have found some aricles that could shed more light on this subject.
I will start posting interesting articles on this thread as i find them.
First interesting
article i found on Trusted.MD
Which plastic water bottles don't leach chemicals?
To be certain that you are choosing a bottle that does not leach, check the recycling symbol on your bottle. If it is a #2 HDPE (high density polyethylene), or a #4 LDPE (low density polyethylene), or a #5 PP (polypropylene), your bottle is fine. The type of plastic bottle in which water is usually sold is usually a #1, and is only recommended for one time use. Do not refill it. Better to use a reusable water bottle, and fill it with your own filtered water from home and keep these single-use bottles out of the landfill.
Unfortunately, those fabulous colourful hard plastic lexan bottles made with polycarbonate plastics and identified by the #7 recycling symbol, may leach BPA. Bisphenol A is a xenoestrogen, a known endocrine disruptor, meaning it disturbs the hormonal messaging in our bodies. Synthetic xenoestrogens are linked to breast cancer and uterine cancer in women, decreased testosterone levels in men, and are particularly devastating to babies and young children. BPA has even been linked to insulin resistance and Type 2 Diabetes
most plastic baby bottles and drinking cups are made with plastics containing Bisphenol A. In 2006 Europe banned all products made for children under age 3 containing BPA, and as of Dec. 2006 the city of San Franscisco followed suit. In March 2007 a billion-dollar class action suit was commenced against Gerber, Playtex, Evenflo, Avent, and Dr. Brown's in Los Angeles superior court for harm done to babies caused by drinking out of baby bottles and sippy cups containing BPA. So, to be certain that your baby is not exposed, use glass bottles.
Article written by Vreni Gurd
Bachelor of Physical and Health Education, High Honours
Holistic Lifestyle Consultant, Level 2, Chek Insitute
Corrective Holistic Exercise Kinesiologist Level 3, Chek Institute
Certified Exercise Physiologist, Canadian Society for Exercise Physiology (CSEP)
Degrees
BPHE, HLC 2, CHEK 3, CSEP-CEP, NSCA, ACSM
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Second article published in Scientific American.
Written by David Biello
Published - February 19, 2008
Food Containers Leach a Potentially Harmful Chemical
Bisphenol A (BPA) is a ubiquitous compound in plastics. First synthesized in 1891, the chemical has become a key building block of plastics from polycarbonate to polyester; in the U.S. alone more than 2.3 billion pounds (1.04 million metric tons) of the stuff is manufactured annually.
BPA is routinely used to line cans to prevent corrosion and food contamination; it also makes plastic cups and baby and other bottles transparent and shatterproof. When the polycarbonate plastics and epoxy resins made from the chemical are exposed to hot liquids, BPA leaches out 55 times faster than it does under normal conditions, according to a new study by Scott Belcher, an endocrine biologist at the University of Cincinnati. "When we added boiling water [to bottles made from polycarbonate] and allowed it to cool, the rate [of leakage] was greatly increased," he says, to a level as high as 32 nanograms per hour.
"It is the unborn baby and children that investigators are most worried about," Newbold says, noting that BPA was linked to increased breast and prostate cancer occurrences, altered menstrual cycles and diabetes in lab mice that were still developing.
Fred vom Saal, a reproductive biologist at the University of Missouri–Columbia, warns that babies likely face the "highest exposure" in human populations, because both baby bottles and infant formula cans likely leach BPA. "In animal studies, the levels that cause harm happen at 10 times below what is common in the U.S." says vom Saal, who also headed the NIH panel that concluded the chemical may pose risks to humans.
"Based on the studies reviewed by FDA, adverse effects occur in animals only at levels of BPA that are far higher orders of magnitude than those to which infants or adults are exposed," says FDA spokeswoman Stephanie Kwisnek. "Therefore, FDA sees no reason to ban or otherwise restrict the uses now authorized at this time."
A new E.U. law (Registration, Evaluation, Authorization and Restriction of Chemical Substances, or REACH), which took effect last year, requires that chemicals, such as BPA, be proved safe. Currently, though, it continues to be used in Europe; the EFSA last year found no reason for alarm based on rodent studies. European scientists cited multigenerational rat studies as reassuring and noted that mouse studies may be flawed because the tiny rodent is more susceptible to estrogens.
For now, U.S. scientists with concerns about BPA recommend that anyone sharing those worries avoid using products made from it: Polycarbonate plastic is clear or colored and typically marked with a number 7 on the bottom, and canned foods such as soups can be purchased in cardboard cartons instead.
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Third article i found was about
Number 1 Plastics -- PET or PETE (polyethylene terephthalate)
Very detailed article written by many scientists - 31 July 2007
Antimony leaching from polyethylene terephthalate (PET) plastic
Please click on the link for the full pdf article
Great article about Antimony leaching from #1 Plastics and the effect of pH, temperature, and interactions with calcium and magnesium
Antimony is a regulated contaminant that poses both acute and chronic health effects in drinking water......
Written by
Paul Westerhoffa
Department of Civil and Environmental Engineering, Arizona State University
Panjai Prapaipong
School of Earth and Space Exploration, Arizona State University
Everett Shock
Department of Chemistry & Biochemistry, Arizona State University
Alice Hillaireaud
Traitement des Eaux et des Nuisances, University of Poitiers, Poitiers, France
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Fourh Atricle
More Evidence That BPA Found In Clear Plastics Impairs Brain Function
Neurology / Neuroscience
Yale School of Medicine researchers reported that the chemical bisphenol-A (BPA), a building block for polycarbonate plastics found in common household items, causes the loss of connections between brain cells. This synaptic loss may cause memory/learning impairments and depression, according to study results published in the Proceedings of the National Academy of Sciences (PNAS).
Unlike previous studies that looked at the effect of BPA on rodents, the team examined the effects in a primate model. They also used lower levels of the chemical than in past studies. "Our goal was to more closely mimic the slow and continuous conditions under which humans would normally be exposed to BPA," said study author Csaba Leranth, M.D., professor in the Department of Obstetrics, Gynecology & Reproductive Sciences and in Neurobiology at Yale. "As a result, this study is more indicative than past research of how BPA may actually affect humans."
Over a 28-day period, Leranth and his team gave each primate 50 micrograms/kg of BPA per day, adjusted for body weight, the amount considered safe for human consumption by the Environmental Protection Agency (EPA). The team also administered estradiol, the major form of hormonal estrogen that modulates nerve cell connections in the brain. Best known as one of the principal hormone products of the ovary, estrogen has also been shown in past studies to be synthesized in the brain, where it aids the development and function of the hippocampus and prefrontal cortex.
The team then used an electron microscope to count nerve cell connections in the brain. They found that BPA inhibits creation of the synaptic connections in the hippocampus and prefrontal cortex, areas of the brain involved with regulation of mood and formation of memory.
"Our primate model indicates that BPA could negatively affect brain function in humans," said study co-author Tibor Hajszan, M.D., associate research scientist in Yale Ob/Gyn. "Based on these new findings, we think the EPA may wish to consider lowering its 'safe daily limit' for human BPA consumption."
Hajszan said that although daily exposure of an average person to BPA usually does not reach the level that was applied in this study, human exposure to BPA is not limited to a single month, but rather is continuous over a lifetime. "The negative effect of BPA may also be amplified when estradiol levels are naturally lower than in healthy adults. That is why exposure to BPA may particularly be risky in the case of babies and the elderly."
Other authors on the study included Klara Szigeti-Buck, Jeremy Bober and Neil J. MacLusky.
The study was supported by the National Institutes of Health and by a National Alliance for Research on Schizophrenia and Depression Young Investigator Award
My Conclusion
After reading many articles and doing research i came to the conclusion that the presence of BPA in trace amouts is ok for adults. If you want to be on the safe side,
do not reuse #1 plastics and do not expose #7 plastics to high heat. I also want to say that this is just my personal opinion.
Hope you gained some knowledge on this topic. If there is anything in here that is incorrect or needs to be adressed. Please feel free to do so.
Thanks.
