Staying ahead of the curve on dust reduction

Operator safety and treatment efficacy are central to SeedGrowth’s ethos. When it comes to dust reduction, that means not just complying with regulations, but going beyond them and always working to find further improvements. Ron Colletti, PhD, SeedGrowth Formulation Specialist and Frank Laubert, Head of Global SeedGrowth Center, explain the dust reduction journey so far…

After a seed has been treated, it is critical that the active ingredients remain on the seed, in an even layer, until the seed is in the soil after planting. This is important for efficacy reasons – because it means the active ingredients are working for the farmer and not being wasted – and it is equally important for safety reasons. Preventing active ingredient particles from being abraded off a treated seed and becoming ‘dust’ in the air is something we must do for the safety of pollinators and people.

The US seed treatment industry has been actively working on dust reduction since 2010, when the American Seed Trade Association formed a working group on dust. What have we achieved in that time, and how much safer are seed treatments today as a result? Ron Colletti, PhD, SeedGrowth Formulation Specialist, is a good person to ask. He has been involved with the topic since the very beginning, first at Monsanto and then at Bayer.

“I remember the early days of the working group,” he recalls. “There were multiple competitive companies present, and at first everyone was being cautious about what information they wanted to share. But everything changed after a few months, when we finally started to share some dust data that we had collected from samples on treated corn, using the Heubach dustmeter.

We quickly reached a surprising conclusion. The only existing dust limit was 0.75g per 100,000 corn seeds, which Europe (ESA, European Seed Association) had set as its target via ESTA (European Seed Treatment Assurance). From the data we had shared, we found that we were already averaging around 0.2g – nearly four times lower than Europe’s target!”

That set a clear precedent: the industry should not merely do the minimum to adhere to regulatory standards, but exceed them, and keep devising ways to exceed them further. “The 0.2g figure is the target we apply for corn internally at Bayer in the US, no matter if regulations permit higher amounts,” explains Ron. The US EPA has not set dust abrasion limits as the US seed industry has been very proactive in promoting stewardship of treated seed. 

Frank Laubert, Head of Bayer Global SGR Center, observed that in Europe, seed treatment quality improved dramatically after the official Heubach dust limit of 0.75g per 100,000 corn seeds was established: since then, people’s awareness on this topic has been growing almost automatically. For instance, in Germany Bayer initiated a study monitoring seed treatment quality in several crops over eight consecutive years. In corn, across all samples (n > 1000) sent in by multiple customer seed plants, the average dust level decreased steadily by more than 65% (from 0.42g in 2009 to 0.14g in 2016). Similar observations were reported from other countries in Europe, where a mix of tailored operator training and dust measurement initiatives proved to be successful in this regard.

“Interestingly, in OSR where we conducted the similar study, the average dust levels never really deviated much from ~0.1g across all years – which has always been way below the official threshold of 0.5 g per 700.000 seeds,” says Frank. “Clearly in OSR, seed companies were already paying high attention to abrasion and consequential seed treatment quality from the very beginning.”

Over the years, Ron has been instrumental in establishing the SeedGrowth approach to dust reduction: one where safety ambitions aren’t something additional for compliance purposes but are at the very center of our offering. Today, samples are regularly taken from our manufacturing sites, sent for Heubach testing, and the resulting data compiled into regular reports, which are shared with our operations and with external partners. Our US manufacturing sites have dust limits of 0.2g for corn and the limit for soy is 0.08g/100,000 seed.  The dust limits for cereals (wheat) and cotton, set by ESTA, are 4g dust per 100kg seed for cereal and 0.75g per 100,000 seed for cotton but will change in 2023 to 6g per 100kg seed for cotton.  Ron believes these limits for cotton and cereals are too high and new treatments that are developed have lower targets. If the dust results are significantly above these figures, the manufacturing site can address the issue, work out what is causing it and determine if any process adjustments can solve it.

“Initially, some of our partners were hesitant to provide samples for testing,” Ron admits. “Before we had any data to show them, they worried that they might get a poor result and have to rework their operation as a result. But it is not about saying the manufacturing process is bad or good, it’s about reinforcing the quality of our product. Farmers and treaters appreciate what we offer and perceive our products as premium. To complete that perception, our seeds and coatings need to be effective and environmentally friendly.”

Now, testing is a universal and welcome process – as is constant innovation to unlock new advances in dust reduction. “It would be easy to say, ‘We addressed it already, so we don’t think about it anymore,’ says Ron. “But we have had a different attitude from the beginning”. When we first engaged with the topic in 2010, there was no regulation on the table in the US. But we recognized that it was time for us to take the lead on the issue – to come together as an industry and answer the big questions about what we were doing about seed dust-abrasion.

“Ever since, we have been committed to our leading role, continually enforcing our own standards and exploring new technologies as well as methods that will harness those technologies to their full potential. For several years, we spearheaded a project to identify ‘de-dusters’: components we could add to formulations whose specific purpose was to lower treated seed dust abrasion. Today, the technology has evolved further: some seed treatment products will contain de-dusters while others, particularly those containing several different active formulations mixed together, will use a polymeric binder that keeps those actives on the seed.

“And this evolution is certainly still on-going. Recently, in our US treatment operations, we changed the timing of application of the polymeric binder, applying it at the end of the treatment process instead of mixing it with everything else. This does a better job of binding the seed treatment materials to the seed and can lead to as much as a 60% reduction in dust.

“We are always looking for the next product innovation, such as biodegradable binders that avoid issues with microplastics (found to be harmful to our environment). We are always testing more aggressively and finding solutions for every stage in the process – not just when seeds are treated or planted, but also when seed boxes or bags are transported, moved around on-site, opened by farmers, and so on. And when we identify a potential improvement, we’re willing to share it and scale it up across the industry, as something of mutual benefit.”

This leads us to the other key element of the industry’s dust reduction mission: collaboration. “It starts with stewardship,” says Ron. “Our SeedGrowth advisors go out to customers and work with them to establish the best hybrids to plant each year. Now, they also give advice on how to run their planters and select the right seed box lubricants to minimize abrasion and maximize singulation. For some hybrids, the seed sizes may be different, so we can advise on the optimal machine settings to ensure reliable, even planting.

“But it goes wider than that. When we identify a potential improvement, we’re willing to share it and scale it up across the industry – that’s what we did with the timing change on binder application. It’s something of benefit to the environment. It doesn’t matter who implements it. As the industry, we must do a good job together.”

It’s an attitude that, thankfully, is shared across the industry. Having initiated the debate on dust reduction, most stakeholders don’t simply want to declare it done and move on – they want to keep being as proactive as possible and advancing towards the next stage of the safety and sustainability journey. “We already meet or exceed all regulations, but our ultimate goal is zero dust,” Ron concludes. “We’re getting closer but need to keep fine-tuning all aspects of the process if we want to reach that goal. At the same time, we need to keep our seeds and seed treatments effective in the field and in treating machines, giving farmers and treaters excellent value as well as safety. Working together, all the way along the value chain, is the best way to make that happen.”