Category Archives: Testing and Data

Reusable Shopping Bags Not Risk Free

The newest fad: The Reusable bag .




Reusable bags are being greatly pushed against the single use plastic bag and people seem to be latching on to the concept. It sounds like a good enough idea, and with all the design options you can really expressive yourself, but is the reusable bag really risk free? Just like many new products there may be some drawbacks that weren’t discovered before becomingso popular and “savior-esque.” The Department of Soil, Water and Environmental Science at the University of Arizona and the School of Public Health at Loma Linda University conducted a study called the Assessment of the Potential for Cross Contamination of Food Products by Reusable Shopping Bags. Now I am going to brief you on the results of this study!

So what is “Cross contamination” ?

Cross contamination occurs when disease-causing microorganisms are transferred from one food to another.

The assessment was divided into 3 Phases

1. Determine the occurrence of bacteria and bacteria of health concern in reusable shopping bags
2. Determine the potential for microbial cross-contamination in reusable shopping bags
3. Evaluate and recommend the washing/bleaching procedures necessary to decontaminate reusable shopping bags

They started off by collecting bags from consumers entering grocery stores in the San Francisco Bay area, Los Angeles and Tucson, Arizona. 84 bags total were collected, 25 from LA, 25 from San Francisco and 34 from Tucson. All but 4 of these bags were woven polypropylene (a little softer than polyester which is what a typical plastic bottle is made out of.) Each bag owner was interviewed on bag usage, storage, and cleaning procedures. (4 unused reusable bags were also purchased and tested)

 

And the Results are in…

Large numbers of bacteria were found in all but 1 bag & coliform bacteria in half.

E-Coli was identified in 12% of the bags & a wide range of enteric bacteria & pathogens.

After meat juices were added to bags & stored in car s for 2 hours, bacteria increased 10-fold.

 

 

How to Clean your bags?

Hand or machine washing was found to reduce the bacteria in bags by >99.9%. So if you clean your bag after every separate use, you should be good! (Don’t forget to think of the water and energy that adds up over time)

 

What were the bag owners habits?

Cleaned bag at home?
97% No
3% Yes

Days bags were used in a Week?
49% 1 day
22% 2 days
18% 3 days
3% 4 days
2% 5 days
3% 6 days
3% 7 days

Bag used Soley for Groceries?
70% Yes
30% No

Other uses of Bag?
57% Other Shopping
19% Clothes
10% Books
9% Snacks
5% Biking Supplies

Separate Bags for Meats & Vegetables?
75% No
25% Yes

Transport in Car?
55% Trunk
45% Backseat

Stored at home?
55% Yes
45% No

 

As you are learning these bags get pretty filthy and are brought back into stores, which is proven to be not at all sanitary. So if reusable bag users do not make the continuous effort to keep their bags clean maybe this isn’t  the cleanest solution to the single-use plastic bag problem, why not explore another option like using Earth friendly  biodegradable and recyclable plastic instead, Like ENSO?

Take a few min to read the rest of the assessment it’s definitely worth your time!
http://www.llu.edu/public-health/news/news-grocery-bags-bacteria.page

 

 

BPI Releases Biodegradation Test Results of Aquamantra Bottles

On Feb 01, 2011 the Biodegradable Products Institute released its biodegradation test results of Aquamantra’s ENSO Biodegradable PET Bottle. BPI which is an industry organization for compostable plastics had the biodegradation tests performed by the highly recognized NSF laboratory.Lab Worker - Testing biodegradation

NSF conducted the biodegradation test of Aquamantra’s biodegradable PET bottle, using ASTM D 5511 Standard Test Method. The ASTM D5511 is a standard test method for determining anaerobic biodegradation of plastic materials under high-solids anaerobic-digestion conditions”.

This ASTM Test Method calculates the amount of carbon dioxide and methane produced during the testing period. The cumulative amount of carbon dioxide and methane evolved from each vessel is calculated and compared to the amount of CO2 and CH4 evolved from blank specimens to determine percent degradation.

After 60 days, the Aquamantra ENSO bottle achieved an overall biodegradation total of 4.47% or 10% of the positive control. As part of the normal biodegradation process with this test method, the biodegradation process drops significantly for both the cellulose and plastic material, shown by the gas generation curve plateauing. Using the test results from this test of 4.47% biodegradation over 60 days and providing an environment with a steady innoculum the test material would fully biodegrade in approximately 3.7 years.

The Aquamantra ENSO bottle utilizes less than half of a percent of active biodegradable ingredients. In other words, the bottle BPI purchased in the market and used for testing was 99.5% PET and .05% biodegradable additive material. Comparing the biodegradation of the Polyethylene material (.37%) the results clearly indicate that biodegradation by microbial assimilation of the ENSO bottle is happening at a rate 8x more than the organic additive within the bottle. By moving the ENSO plastic into a new batch of innoculum biodegradation would continue to happen. There is no indication or scientific reason to imply otherwise.

There were a few notes to keep in mind about this test. The key to performing an effective ASTM D 5511 is in the proper preparation of the innoculum. Many labs are challenged when it comes to preparing a functional innoculum for this test. This is evident when the biodegradation rate of the cellulose material does not reach 70%. In the case of this particular test the cellulose material reached a maximum of 44.31%. Cellulose is a basic material that is normally biodegraded very rapidly and is used as a baseline to validate biodegradation. As stated by NSF, because there was clear biodegradation of the cellulose the the test results are acceptable even though the ASTM D 5511 required minimum of 70% was not obtained.

As a final point; with beginning with a healthy innoculum, biodegradation would have been improved for both the cellulose and ENSO biodegradable bottle; thus resulting in an improved biodegradation timeframe. We recognize that the slower performing innoculum may in someways perform closer to a true landfill environment.

To view the NSF ASTM D 5511 test results please click here.

Pitt Researchers: Plant-Based Plastics Not Necessarily Greener Than Oil-Based Relatives

Biopolymers are the more eco-friendly material, but farming and energy-intense chemical processing means they are dirtier to produce than petroleum-derived plastics, according to study in Environmental Science & Technology

Contact: Morgan Kelly | mekelly@pitt.edu | 412-624-4356 | Cell: 412-897-1400

PITTSBURGH—An analysis of plant and petroleum-derived plastics by University of Pittsburgh researchers suggests that biopolymers are not necessarily better for the environment than their petroleum-based relatives, according to a report in Environmental Science & Technology. The Pitt team found that while biopolymers are the more eco-friendly material, traditional plastics can be less environmentally taxing to produce.

Biopolymers trumped the other plastics for biodegradability, low toxicity, and use of renewable resources. Nonetheless, the farming and chemical processing needed to produce them can devour energy and dump fertilizers and pesticides into the environment, wrote lead author Michaelangelo Tabone (ENG, A&S ’10), who conducted the analysis as an undergraduate student in the lab of Amy Landis, a professor of civil and environmental engineering in Pitt’s Swanson School of Engineering. Tabone and Landis worked with James Cregg, an undergraduate chemistry student in Pitt’s School of Arts and Sciences; and Eric Beckman, codirector of Pitt’s Mascaro Center for Sustainable Innovation and the George M. Bevier Professor of Chemical and Petroleum Engineering in Pitt’s Swanson School. The project was supported by the National Science Foundation.

The researchers examined 12 plastics—seven petroleum-based polymers, four biopolymers, and one hybrid. The team first performed a life-cycle assessment (LCA) on each polymer’s preproduction stage to gauge the environmental and health effects of the energy, raw materials, and chemicals used to create one ounce of plastic pellets. They then checked each plastic in its finished form against principles of green design, including biodegradability, energy efficiency, wastefulness, and toxicity.

Biopolymers were among the more prolific polluters on the path to production, the LCA revealed. The team attributed this to agricultural fertilizers and pesticides, extensive land use for farming, and the intense chemical processing needed to convert plants into plastic. All four biopolymers were the largest contributors to ozone depletion. The two tested forms of sugar-derived polymer—standard polylactic acid (PLA-G) and the type manufactured by Minnesota-based NatureWorks (PLA-NW), the most common sugar-based plastic in the United States—exhibited the maximum contribution to eutrophication, which occurs when overfertilized bodies of water can no longer support life. One type of the corn-based polyhydroyalkanoate, PHA-G, topped the acidification category. In addition, biopolymers exceeded most of the petroleum-based polymers for ecotoxicity and carcinogen emissions.


Once in use, however, biopolymers bested traditional polymers for ecofriendliness. For example, the sugar-based plastic from NatureWorks jumped from the sixth position under the LCA to become the material most in keeping with the standards of green design. On the other hand, the ubiquitous plastic polypropylene (PP)—widely used in packaging—was the cleanest polymer to produce, but sank to ninth place as a sustainable material.

Interestingly, the researchers found that the petroleum-plant hybrid biopolyethylene terephthalate, or B-PET, combines the ills of agriculture with the structural stubbornness of standard plastic to be harmful to produce (12th) and use (8th).

Landis is continuing the project by subjecting the polymers to a full LCA, which will also examine the materials’ environmental impact throughout their use and eventual disposal.

<table style="cursor: default; margin-top: 1em; margin-right: 0px; margin-bottom: 1em; margin-left: 0px; width: 600px; border: 0px dashed #bbbbbb;" border="0" cellspacing="0" cellpadding="0" align="center">
<tbody>
<tr>
<td style="width: 50px; text-align: center;"><strong>Polymer</strong></td>
<td style="width: 50px; text-align: center;"><strong>Material</strong></td>
<td style="width: 10px; text-align: center;">&nbsp;<strong>Green Design Rank</strong></td>
<td style="width: 10px; text-align: center;"><strong>LCA Rank</strong></td>
</tr>
<tr>
<td style="width: 50px;">Polylactic acid-NatureWorks (PLA-NW)</td>
<td style="width: 50px;">Sugar, cornstarch</td>
<td style="width: 10px; text-align: center;">1</td>
<td style="width: 10px; text-align: center;">6</td>
</tr>
<tr>
<td style="width: 50px;">Polyhydroxyalkanoate-Stover (PHA-S)</td>
<td style="width: 50px;">Corn stalks</td>
<td style="width: 10px; text-align: center;">2</td>
<td style="width: 10px; text-align: center;">4</td>
</tr>
<tr>
<td style="width: 50px;">Polyhydroxyalkanoate-General (PHA-G)</td>
<td style="width: 50px;">Corn kernels</td>
<td style="width: 10px; text-align: center;">2</td>
<td style="width: 10px; text-align: center;">8</td>
</tr>
<tr>
<td style="width: 50px;">Polylactic acid-General (PLA-G)</td>
<td style="width: 50px;">Sugar, cornstarch</td>
<td style="width: 10px; text-align: center;">4</td>
<td style="width: 10px; text-align: center;">9</td>
</tr>
<tr>
<td style="width: 50px;">High-density polyethylene (HDPE)</td>
<td style="width: 50px;">Petroleum</td>
<td style="width: 10px; text-align: center;">5</td>
<td style="width: 10px; text-align: center;">2</td>
</tr>
<tr>
<td style="width: 50px;">Polyethylene Terephthalate (PET)</td>
<td style="width: 50px;">Petroleum</td>
<td style="width: 10px; text-align: center;">6</td>
<td style="width: 10px; text-align: center;">10</td>
</tr>
<tr>
<td style="width: 50px;">Low-density polyethylene (LDPE)</td>
<td style="width: 50px;">Petroleum</td>
<td style="width: 10px; text-align: center;">7</td>
<td style="width: 10px; text-align: center;">3</td>
</tr>
<tr>
<td style="width: 50px;">Biopolyethylene terephthalate (B-PET)</td>
<td style="width: 50px;">Petroleum, plants</td>
<td style="width: 10px; text-align: center;">8</td>
<td style="width: 10px; text-align: center;">12</td>
</tr>
<tr>
<td style="width: 50px;">Polypropylene (PP)</td>
<td style="width: 50px;">Fossil fuels</td>
<td style="width: 10px; text-align: center;">9</td>
<td style="width: 10px; text-align: center;">1</td>
</tr>
<tr>
<td style="width: 50px;">General purpose polystyrene (GPPS)</td>
<td style="width: 50px;">Petroleum</td>
<td style="width: 10px; text-align: center;">10</td>
<td style="width: 10px; text-align: center;">5</td>
</tr>
<tr>
<td style="width: 50px;">Polyvinyl chloride (PVC)</td>
<td style="width: 50px;">Chlorine, petroleum</td>
<td style="width: 10px; text-align: center;">11</td>
<td style="width: 10px; text-align: center;">7</td>
</tr>
<tr>
<td style="width: 50px;">Polycarbonate (PC)</td>
<td style="width: 50px;">Petroleum</td>
<td style="width: 10px; text-align: center;">12</td>
<td style="width: 10px; text-align: center;">11<span style="color: #494949; font-family: Verdana, sans-serif; font-size: small;"><span style="font-size: 12px;"><span style="color: #000000; font-family: Verdana, Arial, Helvetica, sans-serif; font-size: x-small;"><span style="font-size: 10px;"><br /></span></span></span></span></td>
</tr>
</tbody>
</table>