PESTICIDES: AN INSIGHT ON THEIR USE AND IMPACT

Why are pesticides so popular?

Pesticides are defined as chemical products designed to protect crops, or other ‘’assets’’, from fungus, insects, weeds and parasites. There are more than 100 families of pesticides, also known under the name of phytosanitary products. All these families contain more than 1,000 active substances.

Today’s massive usage of pesticides results from the chemical revolution that occurred in the first half of the 20^th Century[1] and from strategic decisions of past governments to face demographic growth of their populations and avoid starvation (especially after the World Wars). More mouths to feed meant higher crop yields. Very fast, pesticides appeared to be the solution to neutralize rodents, bugs and parasites attacking the crops.

This enthusiasm for those products is due to their efficiency and easiness of use. Spreading chemicals makes the life of a farmer easier as he needs to spend less time in the fields. More importantly, it allows a significant increase in the productivity and by way of consequence in profitability. That simple equation makes it possible to offer food at a lower price at the end of the production chain[2].

Legally, the acceptance of those components in the crops significantly varies from a country to another, rules are not homogeneous regarding the composition and the quantities allowed, and a lot of freedom is given to producers when it comes to mix pesticides for their activities.

A massive consumption trend all over the world

Conventional agriculture represents 99% of the cultivated areas, and the use of pesticides continues to increase in 2018, despite the increasing number of scientific proofs showing their damage on human health. Even if new studies are published every year, confirming the toxicity and possible sanitary disasters related to their components, they remain today intensively used in the current farming practices worldwide.

In Hong Kong, 95% of the food and beverages are imported, mainly from China, the US and Brazil. These three giants are the largest food producing countries in the world. Yet, they are not the most regulated countries when it comes to safety in food production.

For instance, China is being shaken by regular food scandals related to its cultivating methods. An example among many was with those crops of Fuji apples grown in Yantai (eastern Shandong province, North-East China). The apples were wrapped in paper covered with an illicit pesticide which side-specificity was to make the fruit brighter and smoother[3]. These fruits have even been present on the market of several countries before food safety authorities discovered evidence about their production methods. On another side of the picture, China is also the biggest manufacturer of pesticides worldwide today, one of the most important exporter and one of the biggest user with a yearly consumption of 14.82kg of pesticides/Ha in 2014[4].

In the US, agricultural pesticides expenditures accounted for about $14 billion in 2012. It represented 66% of the pesticide market in the country[5]. Among all of the ones available on the market, 25 are intensively used. The most used and known active substance produced and used in the US is the glyphosate, that became mediatized for its controversial effect on health[6].

Brazil is also one of the biggest consumer of those components. In 2015, the country spent $9.6 billion on agricultural phytosanitary products, counting for about 150 pesticides. Among them, 35 are banned in Europe, considered as too dangerous for health[7].

According to the current European legislation, 385 active substances are allowed in the crops, plus 15 basic substances[8].  As shown in the table below, France had a consumption of 3.9 kg of pesticides/Ha in 2014. 

Source: UN Food and Agricultural Organization (FAO), 2018

Those numbers can be alarming when knowing about the effects of pesticides residues on health. Farmers are the first ones to face the danger of pesticides, but everyone is exposed to them, as they are present in most fruits and vegetables one can find on markets.

Alarmed by the different impacts of such democratization of pesticides and to prevent complications on population health, governments across the world gradually implemented regulations to restrict the quantity and types of pesticides used in farming. In 2008, 109 pesticides – that group more than 500 different active components – were banned in the European Union[9].  In Hong Kong and Mainland China, 36[10] and 39[11] pesticides are respectively banned as of today. They are of 35 banned in the US, in addition to 30 restricted[12][13]. The reasons of their prohibition are their hazardousness on human health but also on other animal and vegetal lives. Despite understanding of their dreadful impacts, overall production and consumption of pesticides keeps growing in the world today.

Effects of pesticides on health 

The endocrine (a hormone) disruptors are the most dangerous type. Half of the pesticides commercialized worldwide and so used in fruits and vegetable production are in this category. Endocrine disruptors impact hormone balance in human body. Hormones are produced in the typhoid, an organ located close to the throat, and are then transported through blood to reach tissues and organs they are meant to support. Endocrine disruptor pesticides entering the body can disrupt the ‘’typhoid axis’’ linking typhoid to organs. They take place in the hormone receptors (think of it as blood vehicles) instead of the real hormones. The consequence is that the latter cannot naturally continue their journey through blood and fulfil their missions, resulting in fertility issues, immune system damages and neurological problems.
Years after its mass introduction in worldwide farming, scientists revealed that the use of these toxic substances was dangerous for health in a certain amount.

Unfortunately, washing your fruits and vegetables (while important!) isn’t much help when it comes to pesticides removal. Many of the pesticides used today are “systemic,” meaning they are taken up by roots and distributed throughout the plant – so no amount of washing will remove them. Fruits and vegetable in conventional farming are the category of products that expose us the most to pesticides residues.  

Pesticides components are invisible from human eyes and act like a poison in the daily life of a consumer: a conventional apple in a supermarket shelf looks almost the same as the organic one displayed next to it. During the grocery shopping journey, the noticeable difference between both is the price indicated under the fruit; a difference which often discourage many consumers. On top of that, organic produce has also to convince beyond its appearance. An organic apple may look – naturally – unperfect, in terms of shapes or colours, compared with conventional ones perfectly round and shiny. All these differences result from the farming methods favouring usage of chemicals to regulate production in conventional agriculture. 

An example is with the production of apples in the US: today an average of 47 different pesticides are used during their growth, 1/3 being classified as hormone disruptors[14]. Chemical residues of these chemicals partly remain in and/or on the fruit when it reaches maturity[15].

Is organic a solution?

Good news coming, all pesticides don’t have the same effect on health and all are not that harmful to the body. Indeed, we can categorize agricultural pesticides in 2 groups: synthetic and natural[16]. Synthetic are the chemical ones created in labs, and natural are substances that occur in nature, like manure for example.

Most of the synthetic pesticides are banned in organic farming, yet not all of them. According to the US and European legislation, 25 active synthetic pest controls are allowed in organic crops, under highly controlled utilization[17].  Before a pesticide is approved for use in organic farming, it has to be assessed for compatibility with a system of sustainable farming, meaning that it has to:

• Be safe to the environment and human health
• Be necessary because of unavailability of natural or organic alternatives
• Be consistent with organic principles[18]

Even if few components are allowed when necessary, organically produced fruits and vegetables have a significant lower level of pesticides residues. They may look less attractive in the outlook, but they are however better for health (and most of the time tastier!)  

Indeed, scientists made several researches to find evidences of a possible health impact,  by comparing the effects of organic versus conventional food consumption[19]. Among them, a recent study conducted by the French National Institute of Agronomic Research highlighted that the biggest consumers of organic food have their cancer risk reduced by 25%. The study has been conducted on 70,000 volunteers during 7 years. During this time, 1,340 cancers have been discovered in the panel, that have then been distributed depending on 4 groups (according to the importance of organic food consumption). The most significant results are on post-menopausal breast cancer, where risk is reduced by 34%, and the lymphoma (type of blood cancer), where risk can be reduced by 76%.

However, one may consider that this study has bias and can be controversial. Indeed, it has been shown that the biggest organic food consumers also have a healthier lifestyle. This group is the one working out on a more regular basis, having a healthier general alimentation and belonging to a higher socio-professional category of citizens. All these elements are very likely to have an impact on the study results [20]. Indeed, the correlation between health and physical activity is not to question. The link exists also between socio-professional status, education level and better overall alimentation.

The use of pesticides is unfortunately still increasing worldwide today, even more in countries having an important demographic or economic growth, and are reaching impressive amounts. Residues are presents in fruits and vegetable we consume and can have a serious impact on our health at different levels. The vast majority of farming being conventional, the probability to encounter pesticides residues and components in what we eat stays high.

Their use in farming of fruits and vegetableshas consequences on the product quality, especially regarding health aspects, but it doesn’t mean that we have to stop eating fruits ! They are rich in vitamins, minerals and micro-nutrients, necessary for a good body functioning. To limit the ingestion of pesticides residues, a good option remains to turn towards organic fruits, definitively less exposed to these components. Even if a bit more expensive due to the stricter production methods (see our article on ORGANIC FOOD to know more about it), it may be worth to make this effort. 

[1] The evolution of chemical pesticides. Fisher scientific. Available on: https://www.fishersci.com [consulted the 16/08/2018]

[2] Eat the peach, not the pesticide. 2015. Available on: https://www.consumerreports.org.  [consulted on 18/08/2018] 

[3] South China Morning Post – Worries grow over Fuji apple fungicide. 2012. Available on: www.scmp.com [consulted on 30/08/2018]

[4] Roser M., Ritchie H. – Fertilizers and pesticides. Available on: https://ourworldindata.org/  [consulted the 20/08/2018]

[5] In the US and the world, pesticide use is up. Available on: http://www.panna.org/. Consulted the 15/11/2018

[6] Pesticides Industry : Sales and Usage. Available on : https://www.epa.gov/. Consulted the 15/11/2018]

[7] Brazil’s pesticide poisoning problem poses global dilemma, say critics. Available on: https://news.mongabay.com/. [consulted the 21/11/2018]

[8] Mie A. & co, 2017 – Human health implications of organic food and organic agriculture: a comprehensive review. Available on: https://ehjournal.biomedcentral.com/. Consulted the 14/11/2018

[9]Which pesticides are banned in Europe? Food and fairness briefing. Pesticide Action Network. Available on: https://www.pan-europe.info/. Consulted the 16/08/2018

[10]Pesticide ordinance, Cap. 133. List of deregistered pesticides, 2017. Available on: https://www.afcd.gov.hk/

[11] China list of banned pesticides to be expanded in 2017 and 18. Available on: http://www.cnchemicals.com/  

[12] Pesticides registration and classification procedures. Available on: https://www.ecfr.gov/. Consulted the 15/11/2018

[13] List of banned or restricted pesticides. Available on: http://scorecard.goodguide.com/ [consulted the 15/11/2018]

[14] Pesticide action Network – food : field to fork. Available on: http://www.panna.org/. [consulted on 30/08/2018]

[15] GreenPeace, 2015 – Pommes empoisonnées : mettre fin à la contamination des vergers par les pesticides grâce à l’agriculture écologique. Available on: www.greenpeace.fr [consulted the 17/08/2018]

[16] Are pesticides in your food harmful for your health? Available on: https://www.healthline.com/ [consulted the 21/08/2018]

[17] What pesticides are allowed. Pesticides Environmental Stewardship. Available on: https://pesticidestewardship.org/. [consulted on 12/08/2018]

[18] Global organics, 2018 – Are pesticides allowed in organic farming? Available on: https://www.global-organics.com/. [consulted on 30/08/2018]  

[19] Mie A., Andersen HR., Gunnarsson S., Kahl J., Kesse-Guyot E., Rembialkowska E., Quaglio G., Grandjean P., 2017 – Human health implications of organic food and agriculture: a comprehensive review. Available on: https://ehjournal.biomedcentral.com/. Consulted the 22/11/2018. 

[20] L’alimentation bio réduit significativement les risques de cancer. Le Monde. [consulted on 23/10/2018]