In praise of PET packaging

In his presentation at the IIP organised conference at The Leela on 21 January the sidelines of Plastivision exhibition Dr Vijay G Habbu said, PET does not does not contain phthalates or EDCs. It does not contain Bisphenol A or other Carcinogens and Antimony leaching from PET bottles is much below the permissible limits. Leaching of lead (Pb) is nil, in contrast to finite quantities from glass bottles. Besides this, Estrogenic reactivity is not conclusively attributed to containers (PET or any other). All packaging materials (Glass, PET, Aluminium, tin,Tetrapacks) exhibit leaching that is dependent on temperature, time and pH of contents.

Habbu stated, packaging is an inevitable part of our lives. And all items for example, electronic goods, food items, pharmaceuticals, books, clothes, letters require packaging.

Packaging is required to fulfil several objectives:

1. Shelf life - maintain the organoleptic properties over a long period

2. Preservation – prevent temperature fluctuations, bacterial ingress, dust

3. Barrier protection – prevent migration of oxygen, water vapour, UV light

4. Physical protection - from shock, vibration, compression

5. Security – prevent pilferage and/or tampering. Also for assuring authenticity

6. Containment or agglomeration - Liquids, powders and granular materials need containment for efficient handling

7. Portion control - Single-serving packaging has a precise amount of contents to control usage

8. Information transmission - Packages and labels communicate how to use, transport, recycle, or dispose of the package or product. Some types of information are required by governments.

9. Traceability – As per Codex Alimentarius Commission 2004 (Codex), traceability has three objectives:

9(a) - to improve supply management

9(b) - to facilitate trace-back for food safety and quality purposes

9(c) - to differentiate and market foods with subtle or undetectable quality attributes

10. Convenience - Packages can have features which add convenience in distribution, handling, stacking, display, sale, opening, reclosing, use, and reuse

11. Marketing - The packaging and labels can be used by marketers to encourage potential buyers to purchase the product

Not hazardous

According to Habbu, PET which was patented on 29 July 1941 does not contain any hazardous chemicals – neither are they used during their conversion into bottles.

He added, PET is a widely used thermoplastic used for the primary packaging of liquid oral formulations intended for certain sections of the population (children, elderly, pregnant women and women in the reproductive age group). The Government of India has permitted the use of PET for packaging of pharmaceuticals.

One reason, he felt PET was so handy was it is stable at high temperatures and a simple material to process. He pointed out how Injection moulding (pre-forms) can be created at 300°C; while Blow Moulding (bottles) can be created at 95-130°C; and film casting is created at 240-300°C.

He added, international regulations also allow PET for pharma packaging mandated by international regulatory bodies like World Health Organisation (WHO), International Conference on Harmonisation, stability guidelines Q1A-Q1F, International Standardisation Organisation (ISO):ISO 22000:2005: Food Safety Management System (FSMS) for ‘Manufacture and dispatch of polyethylene terephthalate (PET) as raw material for food packaging applications’.

Habbu countered the concerns about PET packaging.

1. Lead, Cadmium, Chromium, Arsenic, Mercury, etc. are not needed in the manufacture of PET resin or bottles. Habbu said, these heavy metals are counter-productive as they will affect the clarity of the PET bottles. Hence, they are not used

2. PET neither contains nor needs phthalates of any kind. And even though the word "phthalate" appears in the name polyethylene-terephthalate, PET does not use phthalates

3. Antimony leaching, if any, is well below the migration limits set by the governmental and regulatory bodies of the world. Habbu argued that antimony is used as a catalyst in PET resin manufacture but it is used in a very small level of < 300 ppm in PET resin. Furthermore it is fixed in the polymer matrix.

Habbu stated that PET resins comply with Specific Migration Limit as per - BIS: 12252-1987 (2005); US FDA 21 CFR §177.1630; regulation (EU) 10/2011 on plastic materials and articles intended to come into contact with food.

4. Studies prove that even under abusive conditions, leaching of antimony from PET bottles is well below all permissible limits. Habbu stated, maximum migration levels in beverages at room temperature even after three years of storage will not exceed 2.5 ppb. He also mentioned that diffusion is difficult because of the large molecular size of Antimony Oxide and the highly crystalline nature of PET bottles.

5. Colorants used in Pharma PET bottles are compliant with FDA and other food regulations. He explained how PET conforms to one or more of the following regulations on colorants for food contact materials: US Federal Food, Drug, and Cosmetic Act; US Food and Drug Administration (FDA); and Council of Europe (CoE) Resolution AP (89) 1.

On the use of colorants in plastic materials coming into contact with food: EU regulation 10/2011 on plastic materials and articles intended to come into contact with food; and BIS 9833.

6. PET has a totally different chemistry than polycarbonate and is carcinogen-free.

7. Endocrine Disrupting Chemicals (EDCs) are not used, nor are generated by PET containers.

PET vs glass

In lieu of the glass body approaching the government as well as the industry for supplies of glass bottles to the pharmaceutical companies, Habbu voiced concern over the hike in prices of essential drugs due to logistics plus the transportation costs with glass bottles as packaging material.

The glass industry in India had invested more than Rs.5000 crore in the last five years to create capacities of more than 10,000 tonnes of glass per day which translated into 3.7 million tonnes per annum.This industry is eyeing the pharma market in place of PET.

Therefore Habbu did a detailed comparison between PET raw materials and glass raw materials; and argued that PET is more friendly to health and environment as compared to glass. His two main points were: PET does not contain hazardous substances nor do any leachants cross the allowable limits. And Lead (Pb) leaches out more from glass bottles than PET bottles.

In terms of bottled water when he compared PET vs glass bottle, his findings stated, glass bottles leach a much longer list of elements into water. According to Habbu chemicals like Ce, Zr, Ti, Hf, Th, La, Pr, Fe, Zn, Nd, Sn and Cr show seven to 24 times higher in glass bottles in comparison with corresponding PET bottles.

PET for pharma

Today PET containers are used globally for pharma packing – by international companies and brands.

He showed exampled from round the world as to how PET material used the world over for packaging the most sensitive Liquid Oral Formulations; this included packing liquid formulations meant for the most vulnerable (immuno-deficient) populations.

Not just packing of pharmaceuticals, but these days, PET is safe in more critical and permanent human implants. 394 PET-based products are in use in medical field for several decades and 98 PET-based products in ophthalmic applications.

PET is eco-friendly

Habbu then shared findings from an eco-impact study and pointed out how PET is the most eco-friendly packaging option. He mentioned PET has the lowest carbon footprint compared to glass, aluminium and paper.

A single-serving container systems used for soft drinks:

12 ounce Aluminum Can

8 ounce Glass Bottle

20 ounce PET Bottle

PET is recyclable

PET is completely recycled and has the lowest CFP compared to glass, aluminium and paper.

PET fibres and bottles are converted back into fibres (white); fibres (black or coloured); strappings; cushions, seats; upholstery / curtains; mattresses, pillows. Interestingly enough, amber PET bottles are shred and the flakes are used in making black fibres. While recycling of PET bottle flakes into textile products fetches higher premium than for making bottles.

At the moment 21 billion PET bottles are recycled every year. Even in India, there is an 80% PET recycling rate and more than 50 recyclers.