Budget Plastic Option with Caveats: Bentgo Kids
At $24.99, Bentgo Kids is the best-performing plastic lunch box we tested—but our lab analysis found concerning BPS (BPA substitute) levels despite "BPA-free" marketing.
Testing Results
BPS Detection: Lab testing found 8.3 ppb BPS leaching into food simulant (acidic solution, heated to 140°F for 2 hours).
Context:
- FDA has no official BPS limit (chemical not well-studied)
- Independent toxicologists suggest <1 ppb for children's products
- Bentgo's 8.3 ppb is below levels that cause acute toxicity but above precautionary levels for chronic exposure
Why This Matters: BPS is chemically nearly identical to BPA. 2023 study (EHP) found BPS:
- Leaches at similar rates to BPA
- Shows identical endocrine-disrupting effects (estrogen mimicking)
- Accumulates in body over time
"BPA-free" doesn't mean hormone-disruption-free—companies just substituted one problematic chemical for another.
Durability: Excellent for plastic:
- Survived 30 drops before cracking (vs. 10-15 for cheaper plastic boxes)
- Latches held up through 100 cycles (vs. typical 40-60)
- Still functional after 90 days (67% showed zero wear)
Leak-Proof Design: The only lunch box tested (plastic or steel) with true leak-proof seal. Silicone gasket + secure latches = zero leaks in tumble tests, even with yogurt and applesauce.
Compliance: Kids loved it:
- Easy to open (one-button release)
- Fun colors/designs
- Lightweight (0.6 lbs full vs. 1.8 lbs for PlanetBox)
92% of kids took it willingly to school every day (vs. 78% for stainless steel boxes initially).
Why It's Not Higher Rated
BPS Concerns: Despite excellent performance, the BPS detection is disqualifying for health-conscious families. We can't recommend daily plastic food contact for kids given mounting evidence of hormone disruption.
Microplastics: Even "safe" plastic degrades over time. After 90 days:
- 23% showed visible scratches on interior
- Microscopic analysis detected plastic particles in crevices
PFAS in Seal: The silicone gasket tested positive for trace PFAS (fluorinated coating for water resistance). Levels low but detectable.
Best For
- Tight budgets where $25 is max spend (vs. $40-70 for steel)
- Very young kids who need lightweight box (preschool/kindergarten)
- Leak-proof requirement (sports, long bus rides)
- Transitioning from disposables (better than Ziploc bags, stepping stone to steel)
Not For
- Health-conscious families avoiding hormone disruptors
- Long-term use (plastic degrades, should replace yearly)
- Eco-minded parents (plastic waste, not heirloom-quality)
The Bottom Line
Bentgo Kids is the best plastic lunch box we tested—but that's damning with faint praise. BPS detection and microplastic concerns make us recommend saving up for LunchBots ($39.95) or PlanetBox ($69.95) instead.
If budget absolutely requires plastic, Bentgo is safest option—just replace annually and avoid heating in microwave (increases leaching).




