SEVIN Ant Bug Killer – Pretty Darn Toxic
Sevin Insect Killer Dust is not borax-based. Its active ingredients vary depending on the formulation and have changed over time:
Active Ingredients in Sevin Dust
- Older “Sevin‑5 Ready‑To‑Use 5% Dust” contained 5% carbaryl, a carbamate insecticide.(shop.feldmans-fh.com)
- Current Sevin Insect Killer Dust (ready-to-use) typically contains 0.1% bifenthrin, a synthetic pyrethroid.(Plant Addicts)
- Other Sevin products (e.g., sprays or granules) may use zeta-cypermethrin or combinations of zeta-cypermethrin and bifenthrin as active ingredients.(Cook Feed & Outdoor)
Summary Table
| Formulation | Active Ingredient(s) |
|---|---|
| Sevin‑5 5% Dust (older version) | Carbaryl (5%) |
| Modern Sevin Dust (ready-to-use) | Bifenthrin (0.1%) |
| Some sprays or granules | Zeta-cypermethrin ± Bifenthrin |
Is it Borax-Based?
No. There is no borax or borax-like compound in standard Sevin Dust formulas. Its insecticidal action comes from synthetic neurotoxic chemicals (carbaryl, bifenthrin, or cypermethrin), not from boron compounds or similar minerals.
Additional Context
If you’re considering toxicity or environmental impact:
- Carbaryl (present in older formulations) is known to affect insect nervous systems and has documented risks to reproductive and nervous health in animals.(ameraucanaalliance.org, Plant Addicts)
- Bifenthrin and cypermethrins are synthetic analogs of natural pyrethrins, acting as nerve toxins in insects and, to a lesser extent, in mammals.(ameraucanaalliance.org)
CARBARYL
Yes — carbaryl does break down in soil, but the rate depends heavily on conditions like temperature, moisture, pH, and microbial activity.
Breakdown Mechanism
- Primary route: Microbial degradation by soil bacteria and fungi.
- Secondary route: Hydrolysis (reaction with water), which is faster in alkaline soils.
- Sunlight (photodegradation) plays little role once carbaryl is in soil.
Persistence
- Half-life (time for 50% to degrade) varies:
- Typical range: 4–28 days in moist, biologically active soil.
- Cool, dry, low-microbial soils: can persist 2–3 months.
- Warm, moist, high-organic soils: breakdown can occur within a week.
- Breaks down to 1-naphthol and other metabolites, which themselves are further degraded by microbes.
Mobility in Soil
- Carbaryl binds moderately to soil particles.
- Low leaching potential in clay or organic-rich soils.
- Higher risk of leaching in sandy soils with low organic matter, especially if heavy rain occurs soon after application.
Environmental Notes
- Highly toxic to bees, aquatic invertebrates, and some fish.
- Degradation is slower in anaerobic conditions (e.g., waterlogged soils).
- Even after breakdown, metabolites can be toxic to aquatic organisms if washed into streams.
Here’s the table showing carbaryl soil half-life under different pH, moisture, and temperature conditions.
These values come from EPA pesticide fact sheets, soil degradation studies, and university extension data — they show how soil chemistry and environment greatly affect persistence.
Carbaryl Breakdown in Soil
| Soil pH | Moisture Condition | Temperature | Approx. Half-Life | Notes |
|---|---|---|---|---|
| pH 5 (acidic) | Moist | 25 °C (77 °F) | 10–14 days | Microbial degradation is steady; acidic pH slows hydrolysis. |
| pH 7 (neutral) | Moist | 25 °C | 7–10 days | Fastest microbial breakdown; balanced pH. |
| pH 8.5 (alkaline) | Moist | 25 °C | 2–4 days | Rapid hydrolysis in alkaline conditions; breakdown mostly chemical. |
| pH 5 | Dry | 25 °C | 20–28 days | Low moisture slows microbial activity. |
| pH 7 | Dry | 25 °C | 15–20 days | Still moderate, but slower than moist soils. |
| pH 7 | Moist | 10 °C (50 °F) | 30–60 days | Cold slows microbial metabolism. |
| pH 7 | Moist | 5 °C (41 °F) | 60–90+ days | Very slow breakdown; winter persistence possible. |
| pH 7 | Waterlogged (anaerobic) | 25 °C | 40–80 days | Anaerobic conditions greatly slow degradation. |
Key Points
- Alkaline + moist + warm → fastest breakdown (a few days).
- Cold + dry or anaerobic → longest persistence (months).
- pH is critical because carbaryl hydrolyzes faster at alkaline pH.
- Moisture boosts microbial degradation, but waterlogging slows it.
Bifenthrin (synthetic pyrethroid)
Here’s the bifenthrin soil half-life table in the same style as the carbaryl one, so you can compare persistence side-by-side.
Bifenthrin is much more stable, with degradation dominated by slow microbial breakdown and minimal hydrolysis.
Bifenthrin Breakdown in Soil
| Soil pH | Moisture Condition | Temperature | Approx. Half-Life | Notes |
|---|---|---|---|---|
| pH 5 (acidic) | Moist | 25 °C (77 °F) | 150–250 days | Strong soil binding + low microbial activity in acidic conditions. |
| pH 7 (neutral) | Moist | 25 °C | 97–150 days | Typical agricultural breakdown rate. |
| pH 8.5 (alkaline) | Moist | 25 °C | 90–130 days | Slightly faster microbial degradation at alkaline pH, but still long persistence. |
| pH 7 | Dry | 25 °C | 200–300 days | Low microbial action and photodegradation; extremely persistent. |
| pH 7 | Moist | 10 °C (50 °F) | 250–365+ days | Cold slows microbial metabolism; residues may last over a year. |
| pH 7 | Moist | 5 °C (41 °F) | >365 days | Essentially unchanged after one year in lab tests. |
| pH 7 | Waterlogged (anaerobic) | 25 °C | 200–400 days | Anaerobic environments slow breakdown even more. |
Key Points
- Bifenthrin binds extremely tightly to soil particles — it doesn’t leach but can move with sediment in runoff.
- It is hydrophobic and not easily bioavailable to microbes, which is why it breaks down so slowly.
- Even under ideal warm, moist, neutral pH conditions, it persists many months.
- Under cold or dry conditions, it can last years in soil.
Carbaryl, Bifenthrin, Cypermethrin, Borax
Toxicities pursuant to Precautionary Principle
Got it. Here’s a precaution-first, side-by-side look at carbaryl, bifenthrin, cypermethrin, and borax—focused on toxicity, groundwater risk, persistence, and real-world efficacy.
Quick verdict (precautionary)
- Highest overall hazard outdoors: bifenthrin ≈ cypermethrin (very persistent, extremely toxic to aquatic life/beneficials; runoff risk via sediment).
- Moderate hazard, shorter persistence: carbaryl (broad-spectrum, bee-toxic, moderate leaching potential).
- Lower acute toxicity but real groundwater/salt-load risk: borax (readily dissolves and does leach; chronic boron exposure can harm plants and can affect human health if wells accumulate enough).
Comparative snapshot
| Dimension | Carbaryl | Bifenthrin | Cypermethrins | Borax (borate salts) |
|---|---|---|---|---|
| Primary action | Carbamate AChE inhibitor (neurotoxic) | Pyrethroid (sodium channel modulator; neurotoxic) | Same class as bifenthrin | Metabolic/gut toxin to insects; disrupts enzyme function |
| Kill profile | Fast, broad-spectrum | Very fast knockdown, strong residual | Fast knockdown, residual | Slow kill via baiting (ants/roaches); not a contact killer |
| Soil persistence (typical) | ~1–4 weeks (longer if cold/dry) | ~3–8+ months; can persist ≥1 year | ~1–4+ months | Essentially non-degrading mineral; persists but moves with water |
| Leaching to groundwater | Low–moderate (higher in sandy/low-OM soils) | Very low leaching but moves with eroded sediment | Very low leaching; sediment-bound transport | High (highly soluble; leaches readily) |
| Runoff/Surface-water hazard | Moderate; toxic to aquatic inverts/fish | Very high via sediment; extremely toxic to aquatic life | Very high via sediment; extremely toxic to aquatic life | Can raise boron in surface waters; aquatic plant toxicity at elevated levels |
| Pollinators/beneficials | Highly toxic to bees; broad non-target impacts | Highly toxic to bees; harms many beneficials | Highly toxic to bees; harms many beneficials | Minimal direct bee toxicity (as bait), but sugar baits can attract them—avoid exposure |
| Human acute toxicity (general) | Moderate; cholinergic symptoms possible with overexposure | Low–moderate; paresthesia/neurologic symptoms possible | Low–moderate; similar neuro symptoms | Low acute; ingestion of concentrated borax can cause GI/renal irritation |
| Human chronic concerns (precaution) | Neurobehavioral; possible developmental/reproductive effects at sufficient dose | Neurological; possible endocrine/disruption signals; very persistent exposure potential | Similar to bifenthrin; neurologic; endocrine signals debated | Chronic boron intake can affect kidneys, fertility at high levels; narrow plant tolerance margin |
| Best-use niche (if any) | Targeted outbreaks; avoid bloom periods | Structural perimeter pests where drift/runoff can be controlled | Similar structural uses; avoid garden soils | Indoor, contained ant baits; avoid outdoor soil broadcasting, especially near wells |
Groundwater & wells (what actually seeps)
- Carbaryl: Moderately mobile. In sandy soils/low organic matter and with heavy irrigation or rain soon after application, it can move downward. Typical half-life is short, so repeat applications are the larger concern.
- Bifenthrin & cypermethrin: Do not leach well due to strong sorption, but that’s not “safe”—they ride attached to eroded soil. Any slope + rain = contaminated sediment into ditches, ponds, and streams. That’s disastrous for aquatic invertebrates and fish.
- Borax: Most likely to reach a well. It dissolves easily and travels with percolating water. Even small, repeated outdoor uses (ant mounds, garden) can add boron to shallow groundwater over time.
Human health (precautionary lens)
- Carbaryl: Cholinesterase inhibition—overexposure can cause headache, nausea, salivation, miosis, bradycardia; high doses are medical emergencies. Long-term, protect handlers; keep out of homes, play areas, and edible gardens when possible.
- Bifenthrin / Cypermethrin: Neurologic irritants (skin paresthesia, tingling; high exposures → tremor). Formulations can increase dermal/respiratory uptake. Chronic low-dose signals around neurodevelopment/endocrine endpoints remain a concern; minimize any indoor use and prevent drift.
- Borax: Lower acute hazard, but chronic ingestion at enough dose is a kidney and reproductive risk. The risk pathway is well water in boron-sensitive regions or from cumulative outdoor use. Keep borax strictly as contained indoor bait, never as a lawn/garden dust.
Persistence & ecosystems
- Bifenthrin / Cypermethrin: Longest environmental tail. They suppress beneficial arthropods and can destabilize garden ecosystems for months. Repeated use leads to sediment accumulation.
- Carbaryl: Shorter tail but broad non-target kill (pollinators, predators, aquatic life if carried off-site).
- Borax: Doesn’t degrade; builds in soil water and is phytotoxic above a narrow threshold—plant leaf burn/yellowing shows first.
Efficacy vs. collateral damage (practical guidance)
- If you must use a synthetic: spot-treat only, in dry weather, on flat ground away from drains; never before rain/irrigation; sweep granules/dust off hard surfaces; respect buffer zones from water. Avoid blooms to protect pollinators.
- For home ants/roaches: borax + sugar in sealed bait stations indoors works well (slow, colony-level). Keep away from pets/kids; never broadcast outdoors—protect your well.
- Best overall approach: IPM—seal entry points, remove food/water sources, vacuum/vinegar for trails, caulk, physical barriers, sticky traps. Reserve chemicals for true last resort.
Bottom line (precautionary ranking for a household with a garden and a well)
- Avoid outdoor bifenthrin/cypermethrin unless you can absolutely control runoff and have no pollinator exposure—these are the most environmentally persistent and aquatic-toxic.
- Avoid outdoor borax near any groundwater risk; keep it indoors only in closed bait stations.
- Carbaryl still presents real risks (bees, aquatic life, human neurotoxicity)—if used at all, keep it rare, targeted, and timed to dry weather and non-bloom periods.
- Prefer non-chemical IPM and indoor baiting approaches first.