What do the numbers printed at the bottom of plastic containers mean?

I was at an environmental club association meeting some few weeks back, I got late to the meeting so, unfortunately, I had to sit at the back row. Fortunately though a young beautiful lady was upfront presenting something to the club members, so my concentration was fully on this damsel rather than on what she was presenting, well like the say 'macho hayana pazia', what was i to do anyway...haha', but along those lines of concentration I was able to pick on some few words and that's when I discovered the immense impact her presentation has to any human being. Her presentation was on, how to identify the safety of the plastic containers that we use day in day out like water bottles, to our health and to the environment. I embarked on a simple research on my own on the health, safety and recyclability of the plastics we use in our everyday activities.

Manufacturers have a simple way of classifying plastic containers using a classification method called Resin Identification Code. This code uses numbers to classify plastics based on the material used in their manufacture. These numbers are known as recycling numbers, which range from numbers 1 to 7 and they describe how safe or unsafe the plastic container is to human beings and are always printed at the bottom of these plastic containers. Below is a simple breakdown of these recycling numbers and their recyclability:

Plastic# 1

These are Polyethylene Terephthalate (PETE or PET). They are clear in color and mostly used in disposable beverage and food containers e.g. soda and water. Also found in household cleaning containers. They are considered safe but they allow accumulation of bacteria and when used for hot beverages, could potentially leach into these liquids. They are accepted by recycling programs.

Plastic# 2

High density Polyethylene (HDPE). They are opaque and recyclable. Mostly used in milk jugs, juice bottles, toiletries bottles, and cereal box liners etc. they are considered safe because of their low risk of leaching when used for containing hot substances. They are also accepted by recycling programs.

Plastic# 3

Vinyl or Polyvinyl (V or PVC). Plastic #3 is used in manufacturing of plumbing pipes, detergent bottles and food wrap. These plastics are considered VERY UNSAFE because they may contain phthalates which are linked to numerous health issues ranging from miscarriages to developmental issues. They also contain DEHA, which is carcinogenic. DEHA is linked to other health complications like liver complications and bone mass loss. AVOID plastic# 3 especially where hot foods or liquids are to be used or when the oven has to be used to heat food. They are rarely accepted by recycling programs.

Plastic# 4

Low density Polyethylene (LDPE). Mostly used for manufacture of shopping bags, carpet and squeezable bottles among other more products. It is among those plastics considered safe for use. They are difficult to recycle hence advisable to reuse them.

Plastic# 5

Polypropylene (PP). Used to manufacture microwave safe plastic containers, medicine containers, and yogurt containers. These plastics also lies in the range of plastics considered as safe. It is also accepted by most recycling programs.

Plastic# 6

Polystyrene or Styrofoam (PS). Used to make disposable containers and food wares. Very common also in packaging industries e.g. peanuts packing, manufacture of CD cases etc. These plastics are potential health hazards because of their ease in leaching especially when heated. They tend to leach toxic chemicals. They are not readily accepted by recycling programs and they take ages and ages to decompose.

Plastic# 7

In this category, all other plastics not in the above categories. Usage of these plastics is at your own risk since the chemical composition is unknown. Some of these plastics include the bio plastics, poly-carbonates which have the highly toxic BPA, Bis-phenol-A or the new kid on the block, Bis-phenol- S which is a hormone disruptor which leads to infertility as one of the main complications. Examples are some computer parts, sport equipment, DVDs etc. they are difficult to recycle hence shunned away by most recycling programs.

For all plastic users, now you have an insight of your plastics. Bottom line is, avoid plastic #3, #6 and #7 and where possible, avoid plastic #1. Plastics #2, 4 and 5 are considered safe for human use. However, I personally advice against the use of any plastics because of their contribution to, most of all, environmental degradation especially plastics #4. When it comes to health issues, well, what can I say, the numbers speak for themselves, so fellow earthlings, go back to your kitchens and place every plastic you find upside down on the counter, then check and dispose off any unsafe plastic products, in an environmentally friendly manner if I may add. Furthermore, as the English man says, Better safe than sorry.