Methyl Bromide and Strawberries .. Shock .. Horror .. Oh, Wait a Minute.
April 23, 2016
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Ian Musgrave

There was an article on the ABC site this morning which gave us this alarming headline “Pesticide banned worldwide still used to grow 70pc of Australian strawberries”. Shocking!

Except, well, there were a few teeny tiny but important details missing. Like the fact that the rest of the world is still using the “banned” pesticide too.

Methyl Bromide (the substance involved) has been withdrawn worldwide under the Montreal protocol as it is a potent greenhouse gas (not because of toxicity, as many people have assumed from the headlines). However, world wide, there are exemptions for the use of methyl bromide as a fumigant for quarantine and production purposes (QPS) and some special (critical use) exemptions, it’s not just us. In 2005 Australia, stopped the use of methyl bromide for all but the exempt QPS uses, and for a few uses for which there was no suitable alternative to methyl bromide.

Just like the rest of the world.

In 2012 around 12,000 metric tonnes of methyl bromide were used around the world for various QPS and critical exemption purposes, Australia’s agricultural use was 32 tonnes at this time (Japan’s was 216 metric tonnes and the US 923 metric tonnes for comparison). Critical use exemptions, the ones that allow the strawberry farmers to fumigate their soil, must be applied for each year.

Like everyone else in the world, Australia developed plans to phase out the remaining methyl bromide use. Since 2005, when methyl bromide use in general was phased out, Australia has been replacing methyl bromide in the critical use exemption and (to a more limited extent) QPS categories with alternatives, dropping from 112 metric tonnes in 2005 to 32 metric tonnes in 2015.

Methyl bromide is an important pesticide fumigant, and is used to kill pathogens and pests in imported produce and some produce for export. Finding alternatives is not straight forward, for example, phosphine, one of the alternative fumigants, is highly flammable, so new handing procedures are needed to combat the risk of fire.

While reducing the amount of methyl bromide entering the atmosphere is important, the significant risk to the Australian biota and agricultural production from invasive pests and pathogens has to be weighted against the fact that human produced brominated compounds represent less than 0.03% of the total halogens released into the atmosphere, and that unlike CFC’s, which last in the atmosphere for decades, methyl bromide’s half life in the atmosphere is less than a year.

Given the relatively small impact of methyl bromide, and the continuing reduction of methyl bromide (see here for a comparison of the progress and the contribution of the US vs the rest of the world), Shock! Horror! headlines about Australia’s use for strawberries are unwarranted.

In the strawberry growing industry, methyl bromide is used to destroy pathogens and pests in the soil the strawberry runners are planted in. In Queensland and Tasmania, methyl bromide has been replaced. However, for the soils in the Victorian strawberry growing areas, the alternative fumigants aren’t as effective.

Other fumigants are being researched, but it takes time to find something that is reasonably safe, reasonably cheap and effective. One of the potential replacements, methyl iodide, has been withdrawn from the market, so the hunt is still on for a viable replacement. It may be that we have to grow our strawberries under soil-less conditions to stop disease and pest losses.

So, like all other countries, Australia has phased out methyl bromide, except for quarantine and other critical uses for which there is no effective alternative (again, just like other countries). Since 2005 we have systematically reduced the amount of methyl bromide for these uses, and are undertaking research to reduce the amount even further.

Oh, and in case you are worried that methyl bromide contaminates the strawberries, methyl bromide breaks down in the soil, and the strawberries that grow much later do not come into contact with it. There is no toxicity issue here at all.

The Conversation

Ian Musgrave, Senior lecturer in Pharmacology

This article was originally published on The Conversation. Read the original article.

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The digital world mapped!
July 13, 2015
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We’ve all seen how Mercator maps distort the real size of land masses as they approach the poles. For example, Mercator shows Greenland as being larger than Australia whereas, in reality, Australia is more than 3.5 times larger than Greenland! And we’ve seen political maps that try to divide the goodies from the baddies while simultaneously distorting borders. But this is the first time I’ve seen the world mapped according to the number of online residents.

Digital cartography by the Oxford Internet Institute

Digital cartography by the Oxford Internet Institute

Suddenly, Australia is dwarfed by Japan and even the UK! The USA has all but swallowed Canada! China’s taken all of Russia east of the Urals and Russia itself is now no larger than Germany!

To see a larger and clearer version of the map, click here

Sure China has 1.5 billion people, but that’s not why it now dwarfs Russia, or for that matter, India with it’s 1.3 billion population. It’s because it has vastly more online users than Russia (or India) does. The map scales with each hexagon representing 470,000 online users.

If you subscribe to the theory that internet usage leads to innovation and economic growth – and I do, it’s easy to see where the emerging economies lie. China has plenty of steam left as do South Korea, Taiwan and Japan. But my money is on the future growth of Vietnam, Brazil, the Philippines, Mexico and even Nigeria which, if you look, has subsumed half of the African continent!

What do you think? I’d love to read your comments!

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Recycling – are you doing it wrong?
July 12, 2015
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If your family is like mine, you try hard to recycle every thing possible. Nowadays, our garbage bin is hardly worth walking out for collection because it’s rarely more than 20% full. On the other hand, our recycling bin is always full to overflowing. That’s a ‘feel good’ experience, so imagine my surprise when I discovered I’m making some big mistakes. In fact, mistakes big enough to possibly undermine my recycling efforts!

They might be stamped recyclable, but are they?

They might be stamped recyclable, but are they?

We compost all food scraps. Tick! We separate hard plastics from soft – hard to the recycling bin and soft to the special bins at the supermarket. Tick!  We use all large  cardboard cartons as weed mats and let nature and time compost them. Tick! So where are we going wrong? Hmmmm… lots of places:

Pizza boxes:
My kids get to eat pizza every second Tuesday. The boxes go straight to the recycling bin. Wrong! It turns out that pizza boxes are one of the worst things we could be adding. The reason is the fats and oils the cardboard has absorbed. It’s impossible to remove during the recycling process which results in oily contaminants in the recycled paper. How serious is that? Apparently, very!

All paper products are mixed with water in a large churner during recycling. This separates the oil from the paper fibres but the oil doesn’t dissolve in the water. Instead it gets dispersed throughout all the paper in the mix which results in the ‘new’ paper having visible oil splotches.

And it isn’t just pizza boxes. A lot of take-away food is packed in paper or paper board. Think of fish and chips or fries if you’re a Macca’s fan. It turns out that all of that paper has to go into landfill, not to the recycling depot!

Paper cups:
I profess to not being a fan of coffee in paper cups. I dislike the waxy feel they leave on my lips and I swear I can taste the wax in the coffee. As it turns out, it’s not wax… it’s plastic coating that paper. There are many tens of millions of these cups consumed every day around the world. They’re paper so you ‘do the right thing’ and put them in the recycle bin, right? Wrong! It turns out that coating is every bit as bad as the oils and fats in that pizza box. It just can’t get separated and ends up contaminating everything.

Unfortunately, it doesn’t stop with those coffee cups. Think of all those cold drink containers! The ‘Frozen Cokes’ and ‘Slushees’ and all the post-mix drink containers you get when you eat any type of fast food. They all create the same recycling challenges. In fact, the only things that are easily recycled are the plastic lid and the plastic straw!

Those plastic shopping bags!
We’re lucky. Our major supermarket chains have recycling bins especially for shopping bags. But if you read the notice on the bin, they also list a whole range of other plastics, like food wrappers, biscuit packaging and frozen food bags. On the other hand, our recycling bin has a notice saying “Only hard plastics’. I always assumed they were a different plastic compound but that’s not the reason. It’s all about the sorting process. Air is used to separate paper from plastics and metals. The soft plastics get picked up with the paper and end up contaminating the lot!

So what about the bags? Well, it turns out they also wreak havoc with the conveyor belts, getting caught up everywhere! The problem is so bad that some recycling plants schedule an hour of daily maintenance just to remove the bags from the machinery!

Itty bitty scraps of paper
My zeal to recycle everything I can, also includes every piece of paper, no matter how small. Well, it turns out that that’s another of my big mistakes. Those scraps are close to impossible to separate and they end of being trashed anyway. The solution – for me anyway, is to put all those scraps in a larger paper container, such as an envelope, and put that in the recycling bin. But if you’re using an envelope, make sure it’s paper and not one of those tyvek envelopes which are actually made of polyethylene fibres. Groan!

Here’s a great video from the guys over at SciShow that fully explains the way a recycling plant works. Grab the kids and learn why some things can be and others can’t 🙂

Am I the only recycling zealot to be getting it wrong or have you been making some of these mistakes as well? I’d love to get your feedback. Just look for the comments section below!

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Maximise the life of your Li-ion battery with these four easy tips

Gone are the days when your mobile/cell phone was just that… a phone. We use them as our camera, GPS, weather station, chat tool, browser and, it seems, a zillion other things. The problem, of course, is that all this extraneous use means that when it comes to actually making a call, we may not have any battery power left! Obviously, the first step in conserving battery life is to close all the apps you’re not using right now. Surprise yourself… hold down the home key and see how many apps show up as active!

Lithium Iron Battery Smart Phone

A powerbank is now a must-have in people’s bags to keep their smart phones alive until the end of the day.

Those are measures for surviving the day when you can’t access a power outlet. But with batteries only designed to sustain a certain number of cycles before total failure, how can you ensure maximum performance over the life of the battery?

Here are four tips to keep in mind to maximise your lithium-ion battery’s life span, whether it be for your smart phone, tablet, laptop or your electric car…

 

 

Think of them as dairy products!

Lithium Iron Battery

All batteries deteriorate, whether they are being used or not. This is why manufacturers indicate not just cycle life but also the expected calendar life of a battery. This is similar to the expiration date of dairy products. So when buying a new lithium-ion battery, choose one that has the most recent manufactured date.

Keep batteries at room temperature.

Heat is the biggest factor that reduces the lifespan of a lithium-ion battery. As much as possible, choose an operating environment that is consistently between 20 to 25 degrees Celsius or 60 to 75 degrees Fahrenheit. Warmer environments from the range mentioned cause the protective layer inside the battery to break down. The battery then goes in to self-repair mode as it reconstitutes which, in itself, consumes battery power. When put in colder environments, the chemical reactions inside slow down and this causes a problem on the battery when in use. Just imagine cars during rush hour in a town with many roadblocks.

Partial discharging is better.

Lithium Iron Battery

Most of us would think that partial charging and discharging is bad for batteries. While this is true for nickel cadmium and other older battery types, partial discharging is actually better for lithium-ion batteries. In fact these batteries degrade most when they are kept fully charged. Surprising isn’t it? We’ve been charging our lithium-ion batteries the wrong way!

So if you are going to leave your battery for a long time without use, for example, a business only mobile stored over a weekend, it’s best to keep the charged state low, at around 20 to 40 percent. It also helps to store them in a cool, dry place.

On the other hand, if you’re a heavy user and tend to spend a lot of time tethered to a power point, charging and discharging it a bit at a time, try to keep it close to 50 percent as much as possible. This is better than maintaining batteries at 90 to 100 percent.

BUT, as experts advise, it is best to allow batteries to discharge almost completely AFTER about 30 charges. This is because continuous partial discharging causes “digital memory” which decreases the accuracy of your device’s power gauge. By letting it discharge to the cutoff point before recharging it, you allow its power gauge to be reset.

Lastly for this tip, do NOT completely discharge a battery. If you let your lithium-ion battery discharge below 2.5V per cell, a safety circuit installed inside will be activated and your battery will be “dead”. You won’t be able to charge your battery — only battery analyzers with boost function can recharge batteries that have reached this stage.

No stress.

This last tip is all about power draw. Forcing your battery to provide high power and charge quickly is like heating and cooling simultaneously. You are breaking and rebuilding its protective layer at the same time and this destroys your battery. This habit is one of the fastest ways to decrease you battery’s capacity, so try not to stress your battery out at any one time.

These tips should be taken as general pointers only as, although they apply to the most common types of lithium-ion batteries, there are a few other types which have slightly different characteristics. If in doubt, it is always best to ask the manufacturer for guidance.

Hope that helps 🙂 If you have any other suggestions or tips, why not add them below?

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