Pesticides may harm growing brains


Two neonicotinoid chemicals may affect the developing nervous system in humans, according to the EU.

The European Food Safety Authority (EFSA) proposed that safe levels for exposure be lowered while further research is carried out.

They based their decision on studies that showed the chemicals had an impact on the brains of newborn rats.

bees

One of the pesticides was banned in the EU last April amid concerns over its impact on bee populations.

Neonicotinoids are “systemic” pesticides that make every part of a plant toxic to predators.

They have become very popular across the world over the past two decades as they are considered less harmful to humans and the environment than older chemicals.

But a growing number of research papers have linked the use of these nicotine-like pesticides to a rapid fall in bee numbers.

New levels needed

In April, the European Union introduced a two year moratorium on the use of several types of these chemicals, despite opposition from the UK.

Now EFSA, in a statement, says that it has concerns that two types of neonicotinoids, imidacloprid and acetamiprid, may “affect the developing human nervous system“.

They have proposed that guidance levels for acceptable exposure be lowered while further research is carried out.

The decision has been based on a review of research carried out in rats.

In one study, young rodents exposed to imidacloprid suffered brain shrinkage, weight loss and reduced movement.

In the statement, EFSA said that the two neonicotinoids may “adversely affect the development of neurons and brain structures associated with functions such as learning and memory”.

Current guidelines, it went on, “may not be protective enough to protect against developmental neurotoxicity and should be reduced”.

According to EU Commission health spokesman Frederic Vincent, they would now allow the chemical companies involved to comment on the findings.

“In principle, the next step would then be to amend the reference values,” he said, indicating that this would begin next March.

In their findings, EFSA pointed out that the available evidence had limitations but that they believed the health concerns that have been raised are legitimate.

But other experts said the move by EFSA was more of a precaution than anything else.

“The reduction in the reference values in most cases was modest,” said Prof Alan Boobis, from Imperial College London.

“Whilst there is clearly a question mark over the possible effects of these compounds on the developing brain, the conclusions of EFSA do not suggest that exposure of humans to these compounds at the levels that occur normally in food or in the environment is a cause for concern.

Artificial sweetener ‘is safe’


Artificial sweetener

The artificial sweetener aspartame is safe and poses no threat to health, European food regulators conclude.

The European Food Safety Authority brought forward its review, planned for completion by 2020, at the request of the European Commission.

Since it came into use in the 1980s, a number of medical studies have questioned aspartame’s safety.

The EFSA says it left “no stone unturned” during its full risk assessment.

“Start Quote

Aspartame has been the sweetener with the biggest ‘conspiracy theory‘ stories ever- ranging from behaviour issues in children to liver damage and cancer – all totally disproven, yet again, by this detailed scientific review”

Catherine Collins Principal Dietitian at St George’s Hospital NHS Trust

As well as looking at the available clinical evidence, the EFSA said it listened to stakeholders and considered over 200 comments submitted to its online public consultation.

Full assessment

Aspartame, which sometimes appears on labels as E951, and its breakdown products are safe for human consumption at current levels of exposure, says the EFSA.

Approximately 200 times sweeter than sugar, the low-calorie sweetener is used in many foods and soft drinks.

An Acceptable Daily Intake, or ADI, is set at 40mg per kg of body weight per day.

This is equivalent to 2800mg for an average British adult. For an average 3-year-old child the amount is around 600 mg.

The only exception is for people suffering from a rare genetic disease phenylketonuria who cannot safely consume aspartame.

For most products containing aspartame, consumption would need to be exceptionally high and regular over a person’s lifetime, in order to exceed the ADI.

Dr Alicja Mortensen, who chaired the EFSA’s aspartame review panel, said: “This opinion represents one of the most comprehensive risk assessments of aspartame ever undertaken.

“It’s a step forward in strengthening consumer confidence in the scientific underpinning of the EU food safety system and the regulation of food additives.”

Catherine Collins, Principal Dietitian at St George’s Hospital NHS Trust, welcomed the findings, saying: “Aspartame has been the sweetener with the biggest ‘conspiracy theory’ stories ever- ranging from behaviour issues in children to liver damage and cancer – all totally disproven, yet again, by this detailed scientific review.”

Reports spark row over bee-bothering insecticides.


Pesticide manufacturer brands risk assessment ‘hurried and inadequate’.

Three reports by Europe’s food-safety body have stoked controversy over the possible links between the use of neonicotinoid insecticides and declining bee populations. One leading insecticide manufacturer has attacked the reports, calling them “hurried and inadequate”.

A number of scientific studies have linked neonicotinoids to adverse effects on bee colonies(see Nature video) but some researchers believe that the drop in bee numbers seen in the United States, Europe and elsewhere is attributable to a combination of factors.

Honey trap

The latest assessments from the European Food Safety Authority (EFSA) in Parma, Italy, are based on existing studies of three neonicotinoids: clothianidin, imidacloprid and thiamethoxam. The reports conclude that these chemicals should be used only on crops that are not attractive to honey bees, so that the insects are not exposed to the insecticides through pollen and nectar. Dust and plant sap contaminated with the chemicals may also pose a risk to bees, says the EFSA.

The EFSA is an independent advisory body, and any ban or restrictions on the use of the three chemicals would require legislation by the European Union (EU) or individual nations.

The work has attracted fierce criticism from John Atkin, chief operating officer at thiamethoxam manufacturer Syngenta, which is based in Basel, Switzerland. In a statement, Atkin said, “It is obvious to us that EFSA has found itself under political pressure to produce a hurried and inadequate risk assessment, which even they acknowledge contains a high level of uncertainty. Their report, compiled in under three months, has not taken account of the comprehensive scientific studies that preceded the launch of neonicotinoids, and many years of extensive monitoring in the field.”

EFSA did not respond to Nature‘s enquiries concerning these allegations.

Data gaps

The European Commission welcomed the EFSA’s assessments. The conclusions “are somewhat concerning when it comes to the potential impact of these particular products”, a commission spokesperson said, but “there are still many shortfalls in the scientific data that were analysed”.

Some EU member states are already scrutinizing neonicotinoids. In the United Kingdom, for example, the Department for Environment, Food and Rural Affairs (Defra) has commissioned field studies on the impact of the insecticides on bees. “If it is concluded that restrictions on the use of neonicotinoids are necessary, they will be brought in,” the agency said in a statement.

Bayer, a chemical company based in Leverkusen, Germany, which manufactures imidacloprid and clothianidin, said in a statement that it does not believe that the EFSA’s reports “alter the quality and validity” of previous risk assessments by the EU and member states that have permitted the use of its products. The chemical company pins most of the blame for bee declines on parasitic Varroamites.

Source: nature.com