Spotlight on weedkiller
Use of popular weedkiller Roundup has been called into question again after a landmark court case in the US.
The San Francisco jury granted US$289 million to a groundskeeper who said his lymphoma resulted from years of applying Monsanto’s trademarked Roundup herbicide, which did not include adequate warning of its links to cancer.
The decision prompted Environment Minister Eugenie Sage to ask the Environmental Protection Agency (EPA) to consider adding Roundup to a list of hazardous substances up for reassessment.
Dr Fiona Thomson-Carter,
general manager of New Zealand's EPA's Hazardous Substances
Group, said there is "no change to the science behind our
current position, which is products containing glyphosate
remain safe to use when you follow the instructions on the
New Zealand scientists argued the US ruling shouldn't prompt a knee-jerk ban of Roundup here.
"Herbicide use is seldom exposure to just one specific product - and the dose, duration, type, and frequency of exposure is relevant to any potential risk," Associate Professor Brian Cox, a cancer epidemiologist at the University of Otago told the NZ Herald.
"A sudden reaction to one case in one US law court, that has not yet gone to the appeal court, is not an appropriate method of developing health policy in New Zealand."
is debate over whether or not Roundup causes cancer. Massey
University Centre for Public Health Research Professor John
Potter told The AM Show that
glyphosate — a key ingredient in Roundup - has officially
been designated a "probable carcinogen" by the cancer
research arm of the World Health Organisation: the
International Agency for Research on Cancer (IARC). He said
councils that use the weed killer on verges, greens and
schools should reconsider their use, as should wider
agriculture businesses that use it.
However, Dr Belinda Cridge, a toxicologist from the University of Otago, told the SMC the IARC definition means glyphosate may cause cancer, but there is no evidence of cause and effect and it may only do so only under the right conditions and exposures. Red meat is also listed by IARC as a "probable carcinogen". She said the IARC reviews are "based on good scientific evidence" but that "wider factors are critical to determining full risk".
She acknowledged: "it is very difficult to model and track all possible interactions" of the additives in Roundup and it might be that the combination of these chemicals contributes to cancer — but this isn't something that's been tested yet.
"It's important to consider the whole picture.
Roundup isn’t, and has never been, a safe panacea for all
weed control. Scientists continue to learn more and more
about this chemical and its effects. However, the
alternative options aren’t very appealing and many are
much much worse for both people and the
The SMC gathered expert reaction to the court result and Environment Minister's response.
"It turns out it's kinda harder to [shoot something at the Sun] than you might think, because you've got to bring it rest. Because the Earth is flying through space, you want to slow it down so it will fall towards the Sun.
So what they're doing is flying it to Venus and multiple encounters with the gravity of Venus will shape its orbit cunningly using what's called a slingshot technique, until it flies closer and closer to the surface of the Sun."
Head of the University of
Auckland's Physics Department
Richard Easther on the Parker Solar Probe
Bridge collapse in Italy
A motorway bridge collapse in Genoa this week killed at least 38 people and injured dozens.
This image, posted on twitter by
@antoguerrara, shows the bridge after the
The 200m section of the bridge came tumbling down when one of the huge 90m-high support towers collapsed onto the rail tracks, buildings and river below. Between 30 and 35 cars and three heavy vehicles were on the bridge at the time of the collapse, the BBC reported.
By Thursday (NZ time), the Italian Prime Ministers Giuseppe Conte had declared a 12-month state of emergency in the region. The bridge - known as the Morandi bridge after its designer - is central to the country's motorway system as it connects three ports and travelers from all over the country to the Italian Riviera
Structural engineer Antonio Brencich reportedly warned there were problems with the bridge back in the 1990s and again in 2016, bringing to light a decades-long debate about ageing Italian infrastructure. Engineering Professor Alessandro Palermo from the University of Canterbury knows Brencich and he told Newstalk ZB: "the bridge needed so much maintenance after just 20 years, it would have cost just as much to replace it".
The legacy of the bridge-building frenzy of the mid-20C means "there are a large number of reinforced concrete bridges in Italy, Europe, USA, and Canada with the same age, which are suffering from corrosion of reinforcement and/or pre-stressing tendon," according to Dr Mehdi Kashani from the University of Southampton.
Structural engineer Dr. Demitrios Cotsovos from Heriot-Watt University told the UK SMC that to prevent events like this in future, we need to find out what caused the Morandi bridge to collapse and use that to monitor similar structures globally.
Professor Palermo told Newshub the NZTA has a rigorous maintenance programme for bridges in New Zealand. "They have general inspections every two years, and then they have a more detailed inspection after six years. That also depends on the condition of the bridge [and] where the bridge is located."
The UK SMC asked experts to comment on the disaster.
It'll be ultra-warm till
As a heatwave tapers off in parts of the northern hemisphere, a new forecast system from UK and Dutch researchers has predicted the years 2018 till 2022 are going to anomalously warm, with a greater chance of extreme temperatures.
On top of higher
temperatures caused by climate change, the forecast suggests
the world can expect 'extra warming' in the next few years
because of natural variability, the researchers
These natural changes occur as part of the cooling and heating of the planet's oceans, NIWA's chief scientist of Climate, Atmosphere and Hazards Sam Dean told RNZ.
"The last few years, we've had some really hot years, which were above that trend and this model is predicting that's likely to carry on for a few more years," he said.
The forecast is based on a statistical model that provides reliable predictions of global mean air and sea surface temperatures, taking into account external forces such as greenhouse gases and aerosols, along with natural variability.
James Renwick from Victoria University of Wellington
told Newshub the new 'decadal'
forecast system (which predicts climate in the coming two to
20 years) is at the forefront of climate prediction
"If such forecasts could be made reliably they would clearly be of great value in many sectors: agriculture, energy, emergency management, public health, etc. Most research is focused on using dynamical global climate models (GCMs, as used for climate change simulations), where the ocean state is very carefully specified for the present day."
If the warming trend caused by greenhouse gas emissions continues, years like 2018 will be the norm in the 2040s, Prof Renwick told the NZ Herald, and would be classed as cold by the end of the century.