PhytoremediationOf Lead using Hops

Why Lead? Lead contamination is an incredibly common problem in the

US. It is the #1 contaminant at Superfund sites. The EPA’s RfD Work Group discussed inorganic lead in 1985

and considered it inappropriate to develop an RfD (oral reference dose)for inorganic lead.

The effects of lead, particularly changes in the levels of certain blood enzymes and in aspects of children's neurobehavioral development, may occur at blood lead levels so low as to be essentially without a threshold.

Formation of Research Project Originally designed project and experiments using Hemp:

“In 2013, the Vermont Legislature and Governor Peter Shumlin passed S.157/Act 84, authorizing the cultivation and production of hemp in the State of Vermont, without waiting for the Federal government to relax their regulations prohibiting the cultivation of hemp under the controlled substances act.

Growers of hemp are responsible for verifying that the seeds used are of a type or kind known to produce plants that produce THC below the 0.3% (by dry weight) threshold, and that they may be subject to prosecution under Federal law.”- VT Dept. of Agriculture

Hemp to Hops Both Humulus lupulus (hop) and

Cannabis sativa L. (hemp) are in the Cannabaceae family.

Plants within the same family often perform the same types of functions.

Both Hops and Hemp are phytoextractors and hyperaccumulators, and are heavy metal tolerant.

Hops, unlike Hemp, are legal across the board.

2

NUGGET

Cascade

Fuggle

Phoenix

STERLING

Galaxy

Horizon

Greenburg

Liberty

“Hops” Hop (Humulus lupulus) is

a perennial, dioecious plant that belongs to the Cannabaceae family.

“Hops” is the common term for the female flowers of hop plants, which are known for their use in beer flavoring.

Hemp Lead Accumulation Data

Phytoremediation Phytoremediation is the use of vegetation for in situ

treatment of contaminated soils, sediments, and water.

Traditional Lead Soil “Remediation” Extraction, solidification, soil washing, and acid

washing are common remediation techniques. Often the soil is simply excavated and disposed of, and

even after the above processes, the soil usually cannot be reused and must be disposed of.

Uses chelators (among other chemicals), which make lead more soluble and available for uptake.

Cost can be huge!

Benefits of Phytoremediation Very cost-effective. Low maintenance, low

impact. More aesthetically pleasing. Cons:

Takes considerably more time, in this case years, and exposure can still occur during that time.

Site: McGoff Hill House The inspiration for the project, and the contaminated soil, came from

the house on McGoff Hill. The house had lead paint, and many chips fell in the soil around the

house over the years. Lead levels are so high on the McGoff property that they were required

to be reported to the EPA when soil samples were sent out for testing: 5,000ppm

Uncontaminated soil contains lead concentrations less than 50 ppm but soil lead levels in many urban areas exceed 200 ppm.

The EPA's standard for lead in bare soil in play areas is 400 ppm and 1200 ppm for non-play areas. This regulation applies to cleanup projects using federal funds.

EPA Action Levels on Lead in Soils

Site-Specific Applications of Hops The narrow one meter strip around the foundations of a home, shed or

garage (often referred to as the drip zone) is usually where the most lead contaminated soil can be found.

Hops grows right in that range, and because it has rhizomes (underground stems that function similarly to bulbs), the soil doesn’t need to be disturbed to re-plant from year to year.

Hops need trellis work to grow, and will not break down a house’s exterior (unlike ivy and some other climbing vines).

According to data about both lead toxicity and the accumulation of heavy metals in the Cannabaceae family, I believe it would be unwise to use the hops grown for phytoremediation to brew beer. They should be disposed of alongside the other parts of the plant.

Aesthetics

Growth of Hops Easy to grow, low maintenance. Produces better the second year

(hops cultivation for beer). Will live happily at a height of 6

feet if kept trimmed, will grow to 20 to 30 feet if allowed to.

Likes manure and compost every year.

Many varieties for different areas; cold tolerance, disease resistance, etc.

Added Benefits from Green Cover Having plants growing

near and shading a home will reduce energy (cooling) costs in the summer.

Can help clean the air in urban environments, and other ecosystem services.

Aesthetically pleasing.

Other Phytoremediation Applications of Hops Leftover leaves and stalks are currently being used to remediate

heavy metals in effluents and waste water. The stalks and leaves, which usually go to waste, are ground, and

mixed into a silica-based polymer. They then pack the granules of the polymer, containing chunks of

hop waste, into a glass column through which water containing several common metal pollutants is pumped (including cadmium, chromium, zinc, copper and lead).

The waste plant matter has turned out to be as effective at stripping metal ions out of water as the commercial ion-exchange resins that normally do the job.

Disposal Step one:

Composting Compaction Pyrolysis

Step two: Incineration Direct disposal Ashing Liquid extraction

Out of step two, incineration is proposed as the most feasible, economically acceptable, and environmentally sound.

Questions?

References http://www.sciencedirect.com/science/article/pii/S0926669003001110 http://www.sciencedirect.com/science/article/pii/S0926669002000055 http://

eds.b.ebscohost.com.lsc-proxy.libraries.vsc.edu/ehost/detail/detail?vid=7&sid=e16f8c47-1970-4973-a7c9-b4e926c50e76%40sessionmgr198&hid=114&bdata=JkF1dGhUeXBlPWlwLHVybCx1aWQmc2l0ZT1laG9zdC1saXZl#db=aph&AN=7798029

http://agriculture.vermont.gov/plant_pest/plant_weed/hemp http://www.clu-in.org/download/toolkit/phyto_e.pdf http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2577278/ http://www.iaea.org/inis/collection/NCLCollectionStore/_Public/41/131/41131215.pdf http://www.epa.gov/superfund/remedytech/tsp/download/leadcont.pdf http://www.atsdr.cdc.gov/csem/csem.asp?csem=7&po=8 http://www.cdc.gov/nceh/lead/publications/books/plpyc/contents.htm http://

rydberg.biology.colostate.edu/phytoremediation/2012/Phytoremediation%20with%20hemp%20by%20Laura%20Cascardi.pdf

References Continued https://www.pinterest.com/yorksrealale/beer-ingredients-hops-growing/ http://

www.newscientist.com/article/mg17022853.400-leftover-hops-clean-up-heavymetal-brew.html http://www.sciencedirect.com/science/article/pii/S0269749103003609 http://www.homebrewtalk.com/showthread.php?t=164065