Humans in Public Health: Short-Haul Truckers, Long-Term Noise Exposure

MPH student Rosemelly Jimenez Medal's father has worked as a short-haul trucker for over 25 years, and she noticed that he was struggling to hear conversations at dinner. So Jimenez Medal teamed up with her father and noise researcher Erica Walker, RGSS Assistant Professor of Epidemiology at Brown University, to conduct hearing screenings on short-term truckers in California.

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Rosemelly Jimenez Medal  00:39  

It was actually the summer right before I started here at Brown. They sent us an Excel sheet.  They listed a lot of different professors that were looking at taking on students in different concentrations and in different departments. And Dr. Walker's is the only person that really kind of stood out to me in that list. I sent her an email right away, and I was like, this is the person for me.

Erica Walker 01:03

When she sent me an email, I think I responded in like 10 minutes 

Rosemelly Jimenez Medal 01:06

Yeah, it was right away…

Erica Walker 01:07

And then when I met her, I just immediately connected. It was just, it was a vibe, you know, … She seemed like really, really thirsty for knowledge and really thirsty for experiences. And I just, I just liked her immediately. And I was like, Yeah, I think I think this is gonna work,

Megan Hall 01:22

Rosemelly is part of the Health Equity Scholars Program at Brown’s School of Public Health. The program takes graduates from Historically Black Colleges and Universities, Hispanic Serving Institutions, and local students from Rhode Island. These scholars receive full tuition, a research assistantship, a mentor, and leadership training. 

Megan Hall  01:41  

And Erica, why do you like working with these students so much -the equity scholars?

Erica Walker  01:45  

I think I relate to them, and I understand what they're gonna go through, when they're in a place like Brown. And so when we talk about changing public health, you know making it more accessible, I know that the best way to do that is to take students like Rosemelly, Health Equity Scholars who come from backgrounds similar to mine, and give them the tools where they can go out and impact their communities in a tangible way … going back and saying like, Oh, you know, I can apply these skills to my community, and I can make it better.

Megan Hall 02:16

At Brown, Erica runs the Community Noise Lab, where she researches noise pollution and hearing loss. When Rosemelly first started working with Erica, she helped her run hearing screenings around Providence. 

Rosemelly Jimenez Medal 02:27

And that for me was something that was really exciting because I had never been a part of a process where you were doing the primary data collection.

Megan Hall 02:33

When it came time to pick a topic for Rosemelly’s thesis, Erica suggested looking into hearing loss for auto mechanics - But Rosemelly had some doubts. 

Rosemelly Jimenez Medal 02:41

I said, it might not be possible only because I couldn't figure out a way to ethically access this community, at least in Providence, and in Rhode Island, because I didn't have a direct link, and if we showed up and said, “Hi, we're from Brown, we're here to do research on your hearing, and on what you can and can't hear” it wouldn't have been accepted in the way we wanted it to.

Megan Hall  03:01  

Or you wouldn't have gotten a lot of buy in. They'd be like who are you?

Rosemelly Jimenez Medal  03:04  

Yeah. So then I said, Let me talk to my dad to see if this is something that we can make happen in California.

Megan Hall 03:12

Rosemelly’s dad has been a short haul truck driver in her hometown of LA for more than 20 years - And they have family who work as both mechanics and truck drivers around California. 

Rosemelly Jimenez Medal 03:22

And my dad was like, I don't think we know enough people to recruit the 50 that you need. But then he said, Why not truck drivers? And I was like, You're right. Why not truck drivers?

I remember just like thinking back on conversations growing up, where my mom would tell my dad, like, “Oh, I think you're losing your hearing. I think you're losing your hearing, like you're not hearing what I'm telling you.” And my dad would say, well, the conversation’s not with me, like I'm not nosy, I don't need to hear things that don't concern me. 

Megan Hall 03:50

So that was his cover. 

Rosemelly Jimenez Medal 03:51

It was his cover. So then I came back to Dr. Walker. And I was like, Oh, this is something that my dad kind of shopped around with me if we switch maybe instead of mechanics, and we look at the truck driving community, and we kind of took off since then.

Megan Hall 04:04

Truck drivers are exposed to loud noises all the time. On the road, at loading docks, and at truck yards. Let's listen to some of those sounds and hopefully you can describe to me and give me a sense of how this affects their health. This first one is sound your dad recorded from a cab on the freeway. 

  • Sound clip starts

Megan Hall  04:24  

So how often are truck drivers exposed to this kind of sound?

Rosemelly Jimenez Medal  04:29  

I would say every every day, that's the video that my dad sent me while he was just waiting in traffic or on the road on the typical freeway that someone would use in Southern California.

Megan Hall  04:39

And Erica, how would you describe the sound in terms of decibels or you know, impact on your health?

Erica Walker  04:45 

So we've measured next to major roadways like that a freeway or highway where it could be anywhere from 70 to 95 decibels depending on if horns are honking or you know like driving over potholes or things like that and that definitely puts you in harm's way when it comes to not only hearing but also, you know, cardiovascular events as well.

Megan Hall 05:08

The trucking yard, where Rosemelly’s dad and other drivers eat and socialize at the end of their shifts, is right next to a train line. They hear noises like this - train horn -  all the time…

Erica Walker  05:23  

We've recently measured sound levels in front of a rail line like that. And that can get up to over 100 decibels. And these trains aren't running just twice a day. They're literally running every hour. And they have horns and the horns can be up to 120 decibels.

Rosemelly Jimenez Medal  05:41 

It was a common sentiment among my dad and a lot of other drivers that the train was something that caused a great deal of annoyance to all of them because it just passes constantly during the day. 

Megan Hall  05:51  

So it wasn't just about the sound quality and what it might be doing to their ears, It was that they didn't get any sort of like moment of peace. 

Rosemelly Jimenez Medal  05:57  

No, and especially a lot of the trucking yards are very interestingly placed at exits of freeways, which also disproportionately affects their hearing and just exposes them to a lot of excess sound.

Megan Hall  06:12  

So they can never escape it, it sounds like.

Rosemelly Jimenez Medal  06:14  

No, they're surrounded by it.

Erica Walker  06:16  

If you are exposed to sound levels that are over like 100 decibels, you should only be - with hearing protection - exposed to that sound for like 30 minutes. And can you imagine - they get that in their lunch break, right?

Megan Hall  06:29  

So when you set out the general idea was, “let's do some hearing screenings of truck drivers.” What was your goal? What were you hoping to find out?

Rosemelly Jimenez Medal  06:37 

The original study question was “do truck drivers have an increased risk of occupational hearing loss?” And I was really interested in seeing if truck drivers had worse hearing scores in their left ear compared to their right only because of the proximity of the left ear to the traffic in the window. And something else that I was interested in learning was, does their hearing decline the longer they've worked as truck drivers?

Megan Hall  07:01  

Was there anything that your dad sort of added that made you rethink what you were looking for or how to go about it?

Rosemelly Jimenez Medal  07:06  

It was a really collaborative process. I remember there was one day where her and I were having conversations, and I told her I don't think I can answer this question. Let me just call my dad. So my dad would kind of join from work.

Erica Walker 07:20

He would be in the truck!

Rosemelly Jimenez Medal 07:22

He would be like in his truck at work, and we would just be asking him questions to see how we can kind of go about having this project. 

Rosemelly Jimenez Medal  07:30  

Prior to going to California in July, I kind of really just like mobilized my dad, and I was telling him, hey, my flight is booked, I need to collect at least 50 participants, do you think you can start getting in contact with different family members and really just like word of mouth recruitment? We had gone through a lot of different iterations of how we were going to recruit, we created a number of different flyers that we ran through my dad and eventually he kind of just said, I don't think that would work. After work everyone sits and talks or goes to different food trucks. And that's where those conversations were being had. So my dad did a lot of the recruitment and the heavy lifting before I even got there. So right when I got to California in July, all I had to do was show up to the trucking yards after people were clocked off because he had already had people scheduled on what day they were showing up and how many people we were doing each day.

Megan Hall  08:22  

He was a really great research assistant.

Rosemelly Jimenez Medal  08:25  

Oh 100%. 100% My dad did a lot of the heavy lifting at one specific trucking yard, and then cousins and uncles at other trucking yards recruited. They would all stay behind after work and kind of wait for me to show up and do their testing.

Megan Hall  08:38 

And then what did you discover?

Rosemelly Jimenez Medal  08:41  

I discovered, the drivers do have kind of disproportionate hearing scores and their hearing loss is more profound in their left as opposed to the right, which really confirmed with my study hypothesis. And I was like, Yes!  And also we discovered traffic, the noise from traffic causes an increased risk in hearing loss, and so does having heart problems and high cholesterol.

Megan Hall  09:05  

I know it's, you know, just initial results. But what do they mean for your dad's trucking community?

Rosemelly Jimenez Medal  09:10  

It means that not only do different occupational sounds have an impact on their hearing, but so does their health as well. And that's something that's really important and kind of key to look at, because the primary sample of my research was Latino males. So within the Latino community, there exists a number of comorbidities that they have and they experience. 

Megal Hall 09:34

Obesity, diabetes, and high cholesterol are among the more common other health conditions, or comorbidities in this community. 

Rosemelly Jimenez Medal 09:42

The different comorbidities that they experience have also resulted in an increased risk of occupational hearing loss for them. So we need to develop efforts to kind of help them create healthier lifestyles and access to healthy foods. 

Megan Hall 09:55

In the long term, Rosemelly says her research could lead to programs that add sound proofing to trucks, or help truck drivers make healthier choices.  But she can already point to an immediate result. She says the  process of doing the research had a big impact on her dad…

Rosemelly Jimenez Medal 10:09

After this project, and like the interactive role that he's kind of taken in it, he's going back to school! And he's going back to get his undergraduate degree, which is really exciting.

Megan Hall  10:21  

I think Brown should give him some credits for the work he already did!

Erica Walker  10:24  

We agree!  If anyone can make that happen… Wink wink… Yes!

Rosemelly Jimenez Medal  10:31  

I credited him in the poster that we did last semester, he was credited to my poster. And that was something that was really special. Because even though I sent a picture of the poster, in my family group chat, and they might not really grasp the importance of what it is to be credited as an author on the poster, for me I knew it, I understood. And that was something that was really meaningful for me.

Erica Walker  10:52  

I’m just so proud of you. Thank you. I’m just so proud of you. I'm sorry.

Megan Hall  11:00  

Oh, no! Tell me what you're feeling right now.

Erica Walker  11:03  

I just, I knew who she was two years ago. And I see who she is today. And I'm just like…okay, so I have an artist background and we talk about the process when you make an art piece, and then you know, you sell it and for a little bit of time after that you're like, really,  depressed because you put all of that energy into a project. And you know, it's for someone else's consumption. But I just kind of view the work that we did together. And I see like, wow, I have such a different feeling than I had when I sold art, like, you know, she's graduating in a couple of months, but I just see that she's gonna go out into the world and propagate. And I just know that I'm going to see parts of my work in Rosemelly and Rosemelly is going to make it her own. So I was just moved by that. 

Megan Hall  11:49 

So what is it like to hear that from your mentor?

Rosemelly Jimenez Medal  11:52  

I got really teary eyed listening to it. 

Erica Walker  11:56  

Sorry! But this is why we're here. You can go down pathways that are probably more powerful than you ever could have imagined by just trusting the brilliance of the students and, so I don't know, just seeing that your father there making that contribution is just something I never would have imagined, but I think makes the work all that more powerful.

Rosemelly Jimenez Medal 12:17

Yeah, thank you, I feel like aside from my dad playing such a key role in my thesis, I don't think the project would have been as successful either, if I would have been paired with a different professor to do this kind of work. I appreciated how willing she was to kind of give up the mantle, and allow my dad to kind of make different key decisions. She would say, I'm not an expert in this, but your dad is, refer to your dad on a lot of things. So I don't I don't think it would have been as beautiful as a story as we're kind of uncovering. If it was, if it was with any other people. 

Megan Hall  12:50  

And what's next for you? 

Erica Walker 12:53

A PhD…  

Rosemelly Jimenez Medal  12:54  

a PhD? I would love one. I would love one. I feel like I'm not done learning. But I feel like I would love to work for a few years. And then I'll come back. So Brown, if you'll have me again, listen… 

Erica Walker 13:08

Can I make the admissions decision? You can come back (laughter)

Megan Hall 13:15

Erica Walker is RGSS Assistant Professor of Epidemiology at the Brown University School of Public Health. Rosemelly Jimenez Medal is a second year MPH student concentrating in Epidemiology at the Brown University School of Public Health.