I have answered my own question. Will post the thread i found in the hope it will help others
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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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